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Ontario Geological Survey Open File Report 6143 Georgian Bay Geological Synthesis, Grenville Province: Explanatory Notes for Preliminary Maps P.3548 to P.3552 2004 ONTARIO GEOLOGICAL SURVEY Open File Report 6143 Georgian Bay Geological Synthesis, Grenville Province: Explanatory Notes for Preliminary Maps P.3548 to P.3552 by N.G. Culshaw, D. Corrigan, J.W.F. Ketchum, P. Wallace, N. Wodicka and R.M. Easton 2004 Parts of this publication may be quoted if credit is given. It is recommended that reference to this publication be made in the following form: Culshaw, N.G., Corrigan, D., Ketchum, J.W.F., Wallace, P., Wodicka, N. and Easton, R.M. 2004. Georgian Bay geological synthesis, Grenville Province: Explanatory notes for Preliminary Maps P.3548 to P.3552; Ontario Geological Survey, Open File Report 6143, 28p. This project is part of the five--- year Canada--- Ontario 1985 Mineral Development Agreement (COMDA), a subsidiary agreement to the Economic and Regional Development Agreement (ERDA) signed by the governments of Canada and Ontario. e Queen’s Printer for Ontario, 2004 e Queen’s Printer for Ontario, 2004. Open File Reports of the Ontario Geological Survey are available for viewing at the Mines Library in Sudbury, at the Mines and Minerals Information Centre in Toronto, and at the regional Mines and Minerals office whose district includes the area covered by the report (see below). Copies can be purchased at Publication Sales and the office whose district includes the area covered by the report. Although a particular report may not be in stock at locations other than the Publication Sales office in Sudbury, they can generally be obtained within 3 working days. All telephone, fax, mail and e-mail orders should be directed to the Publication Sales office in Sudbury. Use of VISA or MasterCard ensures the fastest possible service. Cheques or money orders should be made payable to the Minister of Finance. Mines and Minerals Information Centre (MMIC) Macdonald Block, Room M2-17 900 Bay St. Toronto, Ontario M7A 1C3 Tel: (416) 314-3800 Mines Library 933 Ramsey Lake Road, Level A3 Sudbury, Ontario P3E 6B5 Tel: (705) 670-5615 Publication Sales 933 Ramsey Lake Rd., Level A3 Sudbury, Ontario P3E 6B5 Tel: (705) 670-5691(local) 1-888-415-9845(toll-free) (705) 670-5770 [email protected] Fax: E-mail: Regional Mines and Minerals Offices: Kenora - Suite 104, 810 Robertson St., Kenora P9N 4J2 Kirkland Lake - 10 Government Rd. E., Kirkland Lake P2N 1A8 Red Lake - Box 324, Ontario Government Building, Red Lake P0V 2M0 Sault Ste. Marie - 70 Foster Dr., Ste. 200, Sault Ste. Marie P6A 6V8 Southern Ontario - P.O. Bag Service 43, 126 Old Troy Rd., Tweed K0K 3J0 Sudbury - Level B3, 933 Ramsey Lake Rd., Sudbury P3E 6B5 Thunder Bay - Suite B002, 435 James St. S., Thunder Bay P7E 6S7 Timmins - Ontario Government Complex, P.O. Bag 3060, Hwy. 101 East, South Porcupine P0N 1H0 Toronto - MMIC, Macdonald Block, Room M2-17, 900 Bay St., Toronto M7A 1C3 This report has not received a technical edit. Discrepancies may occur for which the Ontario Ministry of Northern Development and Mines does not assume any liability. Source references are included in the report and users are urged to verify critical information. Recommendations and statements of opinions expressed are those of the author or authors and are not to be construed as statements of government policy. If you wish to reproduce any of the text, tables or illustrations in this report, please write for permission to the Team Leader, Publication Services, Ministry of Northern Development and Mines, 933 Ramsey Lake Road, Level B4, Sudbury, Ontario P3E 6B5. Cette publication est disponible en anglais seulement. Parts of this report may be quoted if credit is given. It is recommended that reference be made in the following form: Culshaw, N.G., Corrigan, D., Ketchum, J.W.F., Wallace, P., Wodicka, N. and Easton, R.M. 2004. Georgian Bay geological synthesis, Grenville Province: Explanatory notes for Preliminary Maps P.3548 to P.3552; Ontario Geological Survey, Open File Report 6143, 28p. iii Contents Abstract ............................................................................................................................................................... ix Introduction ......................................................................................................................................................... Overview..................................................................................................................................................... Regional Setting of the Grenville Province in North America ........................................................... Subdivisions of the Grenville Province .............................................................................................. Central Gneiss Belt ..................................................................................................................................... Previous Work ............................................................................................................................................ Terminology................................................................................................................................................ 1 2 2 4 5 5 6 Geology ............................................................................................................................................................... Parautochthon ............................................................................................................................................. Britt Domain (Units 1 to 14)............................................................................................................... Lower Go Home Domain (Units 15 to 18)......................................................................................... Allochthon................................................................................................................................................... Shawanaga Domain (Units 19 to 24).................................................................................................. Sand Bay Gneiss Association .................................................................................................... Ojibway Gneiss Association ...................................................................................................... Upper Go Home Domain (Units 25 to 29) ......................................................................................... Pine Island Gneiss Association .................................................................................................. Pere Brebeuf Gneiss Association............................................................................................... Parry Sound Domain (Units 30 to 41) ................................................................................................ Parry Sound Domain (Basal) ..................................................................................................... Parry Sound Domain (Interior) .................................................................................................. Moon River Subdomain (Units 42 to 46) ........................................................................................... Twelve Mile Bay Gneiss Association ........................................................................................ Moon River Gneiss Association ................................................................................................ Blackstone Lake Gneiss Association ......................................................................................... Discussion ................................................................................................................................................... Cross Section of Central Gneiss Belt Along Georgian Bay: from Active Margin to Collisional Orogen ............................................................................................................................. Active Margin ............................................................................................................................ Collisional Orogen..................................................................................................................... 6 6 6 8 9 9 9 10 10 10 10 10 11 12 13 13 13 13 14 Economic Geology .............................................................................................................................................. Overview..................................................................................................................................................... Mineral Occurrences ................................................................................................................................... Mineral Potential......................................................................................................................................... Parautochthon..................................................................................................................................... Allochthon .......................................................................................................................................... Parry Sound Domain.................................................................................................................. 16 16 16 17 17 17 17 References ........................................................................................................................................................... 17 Appendix 1. Listing of Published Geochronological Data for the Study Area.................................................... 23 Metric Conversion Table ..................................................................................................................................... 28 v 14 15 15 FIGURES 1. Location of the Georgian Bay geological transect and map areas covered by this study............................ 1 2. Location of Central Gneiss Belt; domains are named ................................................................................. 3 3. Cross section of the Central Gneiss Belt along Georgian Bay .................................................................... 14 MAP(S) Map P.3548 Precambrian Geology, Key Harbour Area ................................................................... back pocket Map P.3549 Precambrian Geology, Naiscoot Area.......................................................................... back pocket Map P.3550 Precambrian Geology, Parry Sound Area .................................................................... back pocket Map P.3551 Precambrian Geology, Sans Souci Area ...................................................................... back pocket Map P.3552 Precambrian Geology, Penetanguishene Area ............................................................. back pocket vii Abstract The Grenville Orogen formed during collision of the Laurentian margin and related terranes with an unknown, presumably continental, plate. The Central Gneiss Belt, together with the Grenville Front tectonic zone, forms the structurally lowest part of the Grenville Orogen in central Ontario. Metamorphism, deformation and minor magmatism related to the collision and convergence that formed the Grenville Orogen are recorded in the Central Gneiss Belt during the interval 1160 to 1000 Ma. Essentially, the Central Gneiss Belt consists of a stack of gently-dipping gneissic units (domains) each of which has a distinctive lithological make-up, age of formation, and plutonic and metamorphic history. On account of the highly strained nature of some of the domain boundaries and the evident differences in pre-Grenville history of neighbouring domains, the domains have been interpreted as thrust sheets. Structurally lower domains (polycyclic domains) contain evidence for a pre-Grenville metamorphism, the overlying units (monocyclic domains) do not. The boundary separating the polycyclic and monocyclic domains is termed the Allochthon Boundary Thrust. Several of the domains are made up of subgroupings of consistently associated rock types known as gneiss associations. These components of the domains are not usually separated by structures interpreted as thrusts, and their assembly within the domains therefore predates thrust stacking of domains. Two features of the geology of the Central Gneiss Belt are of special interest: 1. Because metamorphic grade is uniformly upper amphibolite facies or higher the Central Gneiss Belt gives an unrivalled view of processes at mid-depth of a doubly thickened orogenic crust. 2. The similarity of ages and rocks types of the Central Gneiss Belt with those of the Central Plains, Eastern Granite-Rhyolite Province and some southwest USA terranes has long been recognized. Thus, together with these terranes, and much of the Grenville to the northeast, the Central Gneiss Belt was part of a huge active continental margin formed during the Paleo- and Mesoproterozoic. The well-exposed rocks of the Central Gneiss Belt offer insight into the development of this margin before the Grenville Orogen formed. ix Georgian Bay Geological Synthesis, Grenville Province: Explanatory Notes for Preliminary Maps P.3548 to P.3552 N.G. Culshaw1, D. Corrigan1, 2, J.W.F. Ketchum1, 3, P. Wallace1, N. Wodicka1, 2 and R.M. Easton4 Ontario Geological Survey Open File Report 6143 2004 1 Department of Earth Sciences, Dalhousie University, Halifax, Nova Scotia, Canada B3H 3J5 2 Now at Geological Survey of Canada, Ottawa, Ontario K1A OE8 3 Now at GEMOC ARC National Key Centre, Department of Earth and Planetary Sciences, Macquarie University, NSW, 2109, Australia 4 Precambrian Geoscience Section, Ontario Geological Survey Ministry of Northern Development and Mines, Sudbury, Ontario P3E 6B5 Introduction This report is designed to provide additional information with respect to the content and design of Ontario Geological Survey Preliminary Maps P.3548 to P.3552 (Culshaw et al. 2004a-e, back pocket), which provide geological coverage of roughly 140 km of Georgian Bay shoreline from Key Harbour to Port Severn (Figure 1). The mapping results described in this report and on the aforementioned maps were collected as part of a 3-year mapping program, Project C.2.3, Georgian Bay Geological Synthesis, funded as part of the five-year Canada–Ontario 1985 Mineral Development Agreement (COMDA), a subsidiary agreement to the Economic and Regional Development Agreement (ERDA) signed by the governments of Canada and Ontario. The project was carried out in contract with the Geological Survey of Canada. Preliminary results were published by Culshaw et al. (1988, 1989, 1990). Final publication of the maps (Ontario Geological Survey Project 03-006) was assumed by the Ontario Geological Survey in 2003, by mutual agreement with the Geological Survey of Canada. Figure 1. Location of the Georgian Bay geological transect and map areas covered by this study. 1 OVERVIEW The Grenville Province (or Grenville Orogen) was among the first parts of the Canadian Shield mapped in Canada (Logan 1863, 1866), and the first discovery of gold in Ontario was made near Eldorado in 1866. Considerable mapping was done in the Grenville Province in the late 19th century (e.g., Adams and Barlow 1910), and study of the Grenville Province in Ontario contributed to many geologic concepts of the time (Easton 1992). However, as the area became more populated and significant mineral finds were made in northern Ontario, the economic impetus for geologic fieldwork in the Grenville Province diminished. It also soon became apparent that the geology of the Grenville Province was complex. This complexity discouraged many workers, and it is only recently that the study of Precambrian orogenic belts has advanced to the point that we can now begin to unravel the geology of the Grenville Province and to make meaningful comparisons with modern orogens. The most complete recent summary of the Grenville Province in Ontario is that of Easton (1992). Easton and Fyon (1992) and Carter (1984) have provided overviews of the metallogeny of the Grenville Province in Ontario. Regional Setting of the Grenville Province in North America To understand the Grenville Province in Ontario, one must first place it in a regional tectonic setting. Major geologic regions in the midcontinent of central North America are the Southern Province, the Penokean Orogen, the Killarney Magmatic Belt, the Eastern Granite-Rhyolite Province, the Midcontinent Rift System, and the Grenville Province. Metasedimentary and minor metavolcanic rocks of the Huronian Supergroup of the Southern Province underlie the southernmost Canadian Shield between Sault Ste. Marie and the Ottawa River (Bennett, Dressler and Robertson 1991). These rocks were folded and metamorphosed during the circa 1835 Ma Penokean Orogeny (Bickford, Van Schmus and Zeitz 1986). The Huronian rocks southeast of Sudbury are separated from the Grenville Front by plutonic and lesser volcanic rocks of the Killarney Magmatic Belt (van Breemen and Davidson 1988), exposed along an 80 km stretch of the front along Georgian Bay near Killarney, Ontario. These rocks intrude the Huronian Supergroup, and yield U/Pb ages 1750 to 1730 Ma and 1470 to 1450 Ma (van Breemen and Davidson 1988). Southeast of the Grenville Front, Killarney Magmatic Belt rocks have been affected by the Grenville Orogeny. The Killarney granitoids have been interpreted (Easton 1986; van Breemen and Davidson 1988) to be an extension of one of several Mesoproterozoic orogenic belts underlying much of the North American midcontinent west of Ontario. As the northern limit of the Grenville Province is considered to be the Grenville Front, the Killarney Magmatic Belt north of the Grenville Front is not part of the Grenville Province (e.g., Easton 1992). Felsic volcanic rocks and associated plutons of the Eastern Granite-Rhyolite Province form much of the basement beneath the midcontinental United States west of the Grenville Front in southern Michigan, Ohio, and Indiana. These rocks were emplaced between 1480 to 1420 Ma and circa 1350 Ma (Bickford, Van Schmus and Zeitz 1986). Cutting this province is a northwesterly trending belt of gravity and aeromagnetic anomalies interpreted to represent the buried portion of the 1100 Ma Midcontinent Rift (Sutcliffe 1991). The Grenville Front marks the northwest limit of penetrative Grenvillian metamorphism and deformation and truncates structural trends in the adjacent structural provinces, although locally some of these rocks can be traced across the Grenville Front for short distances (10 to 30 km, Easton 1992). It is now generally accepted that this orogenic event (or events) involved northwest-directed thrusting and imbrication of the entire crust, presumably as a result of a terminal collision at about 1100 Ma with a 2 continental landmass somewhere to the southeast (e.g., Rivers et al. 1989; Carr et al. 2000). Many Rb/Sr and K/Ar ages in the Grenville Province range from 1000 to 950 Ma, synchronous with cooling after the Grenville Orogeny. For the rocks exposed in the Grenville Province this paper uses major subdivisions as originally proposed by Wynne-Edwards (1972), as revised by Easton (1992) (see Figure 2). Figure 2. Location of Central Gneiss Belt; domains are named. Georgian Bay transect refers both to the area of shoreline covered by this study, as well as the location of the cross-section shown in Figure 3. Abbreviations: GFTZ, Grenville Front tectonic zone; CMBBZ, Central Metasedimentary Belt boundary zone; CMB, Central Metasedimentary Belt. 3 Subdivisions of the Grenville Province Over the past 40 years, several approaches have been used to subdivide the Grenville Province into lithologic and/or tectonic entities. The subdivision of the Grenville used here (Figure 2) has drawn from several previous subdivisions in particular, Wynne-Edwards (1972), Davidson, Culshaw and Nadeau (1982), and Easton (1992). The Grenville Province in Ontario consists of 2 main divisions: the Central Gneiss Belt and the Central Metasedimentary Belt (see Figure 2) (Wynne-Edwards 1972). The Grenville Front separates the Grenville Province from older units to the north and northwest. That part of the Central Gneiss Belt that lies within 20 to 30 km of the Grenville Front has been termed the Grenville Front tectonic zone (e.g., Wynne-Edwards 1972; Rivers et al. 1989). The zone consists of deformed and metamorphosed rocks derived from the Southern and Superior Provinces and the Killarney Magmatic Belt and is characterized by northeast-trending zones of cataclasis, northeast-trending foliations, and by a prominent southeastplunging lineation (Easton 1992). The Grenville Front tectonic zone, which includes the Grenville Front Boundary Fault, and the Central Metasedimentary Belt boundary zone, which separates the Central Gneiss Belt from the Central Metasedsimentary Belt (see Figure 2), are major shear zones several kilometres in width, characterized by strongly deformed rocks with northeasterly trending, moderately to shallowly southeast-dipping tectonic layering, and southeast-plunging mineral lineations. Mylonites are locally developed. Marble tectonic breccia, containing fragments of metasedimentary, plutonic, and amphibolite rocks is common within, and adjacent to the eastern margin of the Central Metasedimentary Belt boundary zone. Significantly the 2 zones are subparallel in Ontario (see Figure 2). Similar subparallel zones of intense deformation on a smaller scale form boundaries between lithotectonic terranes and domains within both the Central Gneiss Belt and the Central Metasedimentary Belt (see Figure 2). The Central Gneiss Belt and parts of the Central Metasedimentary Belt boundary zone, consist mainly of quartzofeldspathic gneissic rocks that have generally been metamorphosed to upper amphibolite facies, and locally to granulite facies. Most of these gneisses are believed to be plutonic in origin, with subordinate amounts of metasedimentary gneiss. In Ontario, the dominant structures and foliations in these rocks are northeasterly, and these trends are very evident on aeromagnetic maps of the area. The Central Gneiss Belt consists of a variety of Archean to Mesoproterozoic crustal segments, all of which have been affected by the Grenville Orogeny (Easton 1986, 1992). Crustal material of 3 main ages is present (Easton 1986, 1992; Dickin and McNutt 1989). North of the French River, reworked Archean and Paleoproterozoic gneisses are intruded by Mesoproterozoic (1250 to 1500 Ma) plutonic rocks, with granitic and monzonitic rocks predominant. The bulk of the Central Gneiss Belt consists of Mesoproterozoic gneisses (1600 to 1800 Ma) intruded by 1400 to 1500 Ma granitic and monzonitic plutons. The Parry Sound domain (see Figure 2) consists of mafic to intermediate composition rocks formed from at about 1350 to 1450 Ma (Dickin and McNutt 1989; Wodicka, Parrish and Jamieson 1996). Distinctive lithotectonic terranes, some further subdivided into domains, have been identified with the Central Gneiss Belt (e.g., Culshaw, Davidson and Nadeau 1983; Easton 1992) (see Figure 2). The terranes and domains are distinguished by differences in their rock assemblages, internal structure, metamorphic grade, and locally by geophysical signature. They are bounded by zones of intensely deformed and sheared rocks characterized by layering that can be traced for many tens of kilometres. The Central Gneiss Belt is described in greater detail in the next section of the report. The Central Metasedimentary Belt lies southeast of the Central Gneiss Belt (see Figure 2), and is a major Mesoproterozoic accumulation of metavolcanic and siliciclastic and carbonate metasedimentary 4 rocks. The supracrustal rocks comprise the classical Grenville Supergroup, which consists of a variety of formations and groups, as outlined in Easton (1992). The supracrustal rocks have been invaded by a variety of compositionally diverse syntectonic, late-tectonic, and post-tectonic plutonic rocks, and the entire succession has been metamorphosed at grades ranging from greenschist to granulite facies. The Central Metasedimentary Belt can be divided into several lithotectonic terranes characterized by differences in lithology, geologic history, structural history, and ages of metamorphism and plutonism (e.g., Easton 1992). The Elzevir and Bancroft Terranes, which include the Grenville Supergroup, are characterized by volcanism and sedimentation between 1300 and 1250 Ma, followed by plutonism and metamorphism at 1240 to 1250 Ma and again at 1100 to 1070 Ma. In contrast, the Frontenac Terrane lacks volcanic rocks, and was subjected to plutonism and metamorphism at roughly 1170 to 1160 Ma. CENTRAL GNEISS BELT The Grenville Orogen formed during collision of the Laurentian margin and related terranes with an unknown, presumably continental, plate. The Central Gneiss Belt (CGB), together with the Grenville Front tectonic zone, forms the structurally lowest part of the Grenville Orogen in central Ontario. Metamorphism, deformation and minor magmatism related to the collision and convergence that formed the Grenville Orogen are recorded in the Central Gneiss Belt during the interval 1160 to 1000 Ma (see Culshaw et al. (1997) and Carr et al. (2000) for further details). Essentially, the Central Gneiss Belt consists of a stack of gently dipping gneissic units (domains) each of which has a distinctive lithological make-up, age of formation, and plutonic and metamorphic history. On account of the highly strained nature of some of the domain boundaries and the evident differences in pre-Grenville history of neighbouring domains, the domains have been interpreted as thrust sheets. Structurally lower domains (polycyclic domains) contain evidence for a pre-Grenville metamorphism, the overlying units (monocyclic domains) do not (see Figure 2). The boundary separating the polycyclic and monocyclic domains is termed the Allochthon Boundary Thrust (Rivers et al. 1989; Ketchum and Davidson 2000). Several of the domains are made up of subgroupings of consistently associated rock types known as gneiss associations. These components of the domains are not usually separated by structures interpreted as thrusts and their assembly within the domains therefore predates thrust stacking of domains. Two features of the geology of the Central Gneiss Belt are of special interest: 1. Because metamorphic grade is uniformly upper amphibolite facies or higher, the Central Gneiss Belt gives an unrivalled view of processes at mid-depth of a doubly thickened orogenic crust. 2. The similarity of ages and rocks types of the Central Gneiss Belt with those of the Central Plains, Eastern Granite-Rhyolite Province and some southwest USA terranes has long been recognized (Easton 1986). Thus, together with these terranes, and much of the Grenville to the northeast, the Central Gneiss Belt was part of a huge active continental margin formed during the Paleo- and Mesoproterozoic. The well-exposed rocks of the Central Gneiss Belt offer insight into the development of this margin before the Grenville Orogen formed. PREVIOUS WORK A traverse of the shore of Georgian Bay was made by Alexander Murray in 1848 (Murray 1850, p.45 to 46), and again by Robert Bell in 1876 (Bell 1878, p.198 to 207). The International Geological Congress had a field excursion in the Parry Sound area in 1913, and examined some localities on Parry Island (Walker 1913, p.98 to 100). Most previous work in the study area has focussed on the immediate area surrounding Parry Sound, with Coleman (1894, p.98 to 100; Coleman 1899, p.259 to 260), Satterly (1943) and Hewitt (1967) describing the geology and mineral occurrences of the Parry Sound area. More 5 recently, the Ontario Geological Survey published a series of 1:50 000 scale compilation maps for the Muskoka domain and its environs (Lumbers and Vertolli 2000a-g). Of this series of maps, 3 sheets, 31D/13, 31E/4 and 31E/5 (Lumbers and Vertolli 2000c, 2000e, 2000g) overlap with parts of maps P.3550, P.3551 and P.3552 (see back pocket). Regional geological mapping of the western Central Gneiss Belt in Ontario by Davidson, Culshaw and Nadeau (1982) and Culshaw, Davidson and Nadeau (1983) led to the recognition of the tectonic significance of regional high-strain zones in the area, and established the basic tectonic framework of terranes and domains that is utilized in this report (see Figure 2). TERMINOLOGY Terminology for all plutonic rocks in the area follows that of Streckeisen (1976). For metamorphic rocks, mineral prefixes are listed in order of relative abundance, starting with least abundant first. Mineral abbreviations follow Kretz (1983). The following conventions are used regarding descriptive adjectives. A gneissic granite is a meta-igneous rock of granitic composition. A granitic gneiss, a granite gneiss, or a gneiss of granitic composition may be either a meta-igneous or a metasedimentary rock. Similarly, a tonalitic gneiss or a tonalite gneiss is a gneiss of tonalite modal composition, but may be of either metaigneous or metasedimentary origin. A gneissic meta-arkose is a metasedimentary gneiss of overall granitic composition. The term metamorphic grade is used in the case where bulk-rock composition or other factors prevent a more detailed assignment of metamorphic conditions. Where metamorphic conditions can be outlined more precisely, the metamorphic facies terminology of Turner (1981) is used. Culshaw et al. (1988) introduced the concept of “gneiss associations” for mapping highly deformed and metamorphosed rocks of the Central Gneiss Belt. A “gneiss association” is an informal stratigraphic term that is primarily lithological, but which also may contain information with respect to plutonic history, metamorphism or mafic diking. If it were decided to formally name a “gneiss association” as a lithodemic unit under the North American Stratigraphic Code (NACSN 1983), in most cases, they would correspond to a suite or a complex. Geology PARAUTOCHTHON Britt Domain (Units 1 to 14) The Britt domain has a considerable range of protolith ages, including circa 1800 to 1600 Ma granitic orthogneiss cut by 1460 to 1430 Ma megacrystic granitoids (single cycle plutonic rocks). The polycyclic nature of the Britt domain is clearly shown by the following relationship that is very common in the older (1800-1600 Ma) group of gneisses: diabase dikes, deformed and metamorphosed in the Grenville orogenic cycle, cut circa 1450 Ma leucosomes (Culshaw et al. 1989, Ketchum et al. 1994). The metadiabase dikes have close affinities to the circa 1235 Ma northwest-striking Sudbury diabase dike swarm on the Laurentian foreland (Ketchum and Davidson 2000). The range of U-Pb crystallization ages as well as Nd model ages older than 1800 Ma (Dickin and McNutt 1989) clearly tie the gneisses to 6 undeformed rocks of comparable age in the US midcontinent (Easton 1986) and imply their Laurentian affinity (Culshaw et al. 1997; Carr et al. 2000). In the map area several recognizable rock associations comprise the Britt domain: the Bustard Islands (unit 1), Key Harbour (units 2 to 5), Bayfield (units 6 to 8) and Nadeau Island (units 9 to 14) gneiss associations. All the aforementioned gneiss associations may represent separate phases in the evolution of an Andean-type arc and back-arc complex that formed at the southeastern continental margin of Laurentia in 2 distinct stages of crustal growth at 1800 to 1600 Ma and 1460 to 1430 Ma (Carr et al. 2000; Slagstad 2003). Understanding the detailed significance of these groupings awaits further work. The most prominent member of the Bustard Islands gneiss association is a medium-grained, moderately foliated, migmatitic granodiorite-tonalite orthogneiss that contains many amphibolite lenses and layers, probably metamorphosed mafic dikes. The age of the orthogneiss is not known but the absence of a leucosome older than the dikes may imply a Mesoproterozoic age for the orthogneiss. This interpretation is supported by presence in the area (but not indicated on Map P.3548, back pocket) of lesser amounts of polycyclic gneiss with metadiabase dikes cutting older leucosomes. The Key Harbour gneiss association is best exposed in the islands southwest of Key Harbour where all the compositional varieties are exposed. The most extensive unit is a pink migmatitic granite orthogneiss (unit 4) emplaced at circa 1690 Ma (Corrigan, Culshaw and Mortensen 1994). There are undated tonalitic orthogneiss and metasedimentary rocks that predate the granite. Mafic gneiss (metagabbro, monzodiorite)(unit 3), located south of Henvey Inlet to south of Byng Inlet, have been included in the Key Harbour gneiss association although contact relations are unknown. It is possible they are part of the Mesoproterozoic plutonic suite. Some metasedimentary rocks (unit 2) contain corundum, in addition to kyanite and sillimanite, as in the Nadeau Island gneiss association (see below). Along Highway 69 the Key Harbour gneiss association is represented by migmatitic layered grey gneisses of varied character (unit 5). These may be related to the older tonalitic gneisses present near Key Harbour. Monazite cooling ages of circa 1035 Ma (Corrigan, Culshaw and Mortensen 1994) are the best estimate for the age of Grenvillian upper amphibolite facies metamorphism. The most voluminous member of the Bayfield gneiss association is a grey hornblende-bearing tonalitic orthogneiss (unit 7b). A granodiorite lacking hornblende, but commonly with recrystallised potassium feldspar megacrysts (unit 7a), is part of the same suite and locally (e.g., Meneilly Island) has patches partly retrogressed from granulite facies. Semi-pelitic and pelitic gneiss forms a mappable horizon (unit 6) in the south, otherwise the Bayfield gneiss association is poor in metasedimentary rocks. Pink leucocratic gneiss is a prominent member that is of potential supracrustal origin, and forms 2 large bodies, centred on Bayfield and along the margin of the Britt pluton. There are comparable bodies of pink leucocratic gneiss in most other domains along Georgian Bay and may represent one or more events common to all domains (Culshaw and Dostal 2002). The Nadeau Island gneiss association has more lithological variation than the Bayfield gneiss association. The polycyclic orthogneiss in both gneiss associations are similar. There are, however, a greater number of mappable metsedimentary intervals in the Nadeau Island gneiss association, and small metasedimentary units (smaller than map scale) are common. In the north, close to Pointe-au-Baril channel, there are occurrences of corundum-bearing metasedimentary rocks in the Bayfield gneiss association. Small areas of preserved and partly retrogressed granulite facies rocks are relatively common throughout the gneiss association. Good examples occur along Highway 69 where, within tonalitic orthogneiss, mafic horizons contain relict orthopyroxene. Fresh mafic granulite occurs at Raspberry Island. The age of the Mesoproterozoic metamorphism, including formation of the mafic granulites, is estimated at 1450 to 1430 Ma (Tuccillo et al. 1992; Ketchum et al. 1998). Metasedimentary rocks 7 contain kyanite and sillimanite and Grenvillian metamorphic conditions are estimated at 700 to 800oC and 10 to 12 kbars (Ketchum et al. 1994) The Britt domain is host to 2 intrusive complexes of Mesoproterozoic granitoid bodies. These bodies (unit 50) are sheet-like, commonly megacrystic, and have emplacement ages of 1460 to 1430 Ma (van Breemen et al. 1986; Corrigan, Culshaw and Mortensen 1994). In the Key Harbour gneiss association the intrusive complex is dominated by the monzogranitic Britt pluton, but includes granodiorite, granite, syenite and leucogabbro bodies. There are numerous small gabbroic bodies well exposed in the islands near Key Harbour, one of which is dated at greater than 1454 Ma (Davidson and van Breemen 2001), suggesting a potential link with the granitoid plutons. The Pointe-au-Baril intrusive complex lies within the Nadeau Island gneiss association. The Pointe-au-Baril intrusive complex is entirely granitoid, lacking the more extreme compositional varieties present near Key Harbour. Pink leucocratic gneiss (unit 52), of the type found throughout the synthesis area, is present in the Britt domain both as mappable units and as outcrops that are too small to map. Along Highway 69, pink leucocratic rock demonstrably crosscuts pre-Grenvillian leucosome, but, for the most part, no clear age relationship is demonstrable between pink leucocratic gneiss and the surrounding rocks. The major structural features of the Britt domain are large horizontal upright folds with southeast trending hinges. These folds generally deform an older Grenvillian fabric and have hinges parallel to a lineation that indicates the direction of maximum extension. Although the enveloping surfaces of the folds are gently dipping, the folds terminate in steep zones: for example, at the southeast margin of the Grenville Front tectonic zone (around the Bustard Islands) and at the southeastern extremity of the Britt Pluton, within the Bayfield gneiss association. Lower Go Home Domain (Units 15 to 18) The lower Go Home domain is dominated by Mesoproterozoic megacrystic granitoid rocks (circa 1460 Ma; T.E. Krogh, geochronologist, Jack Satterly Geochronology Laboratory, personal communication, 1991). These, together with coronitic gabbro bodies and numerous other, minor mafic bodies cut migmatitic granitoid gneisses that were likely emplaced at circa 1600 Ma (T.E. Krogh, geochronologist, Jack Satterly Geochronology Laboratory, personal communication, 1991). There are other units of unknown age, including strongly deformed metaplutonic rocks, as well as minor pelitic gneisses and thin, but laterally extensive, marbles (Culshaw et al. 1990, 1997). The presence of the Mesoproterozoic megacrystic granitoids cutting gneisses containing pre-granitoid leucosome is comparable to relative age relationships observed in the Britt domain and establishes the lower Go Home domain as part of the polycyclic, parautochthonous Laurentian craton (Culshaw et al. 1997; Carr et al. 2000). The internal structure of the lower Go Home domain is marked by the presence of open, upright and subhorizontal folds of gneissosity comparable to folds in other domains. The boundary relations with overlying domains are complex. The boundary with the upper Go Home domain is marked by small (commonly metre-scale) anorthosite gneiss bodies and garnet amphibolite pods of similar size that are in places demonstrably retrogressed eclogites. Gneissosity above and below the boundary is concordant. The boundary of the Moon River subdomain and the lower Go Home domain is comparable, being marked by a continuous anorthosite sheet and several small (metre to centimetre scale) anorthosite bodies. In several locations gneissosity is discordant across the boundary. The 2 boundaries meet in a triple point on Highway 69, just south of the Moon River Bridge (see Map P.3551, back pocket), suggesting that the upper Go Home domain pinches out southeastward beneath the Moon River subdomain. 8 ALLOCHTHON Shawanaga Domain (Units 19 to 24) The Shawanaga domain along Georgian Bay consists of a large nappe formed of the metasupracrustal Sand Bay and metaplutonic Ojibway gneiss associations (Culshaw et al. 1989). The entire domain has been metamorphosed to upper amphibolite facies, at greater than 700°C and 10 to 12 kbar (Wodicka, Ketchum and Jamieson 2000). Deformation and high-grade polyphase metamorphism took place between about 1090 and 1050 Ma (Culshaw et al. 1997; Wodicka, Ketchum and Jamieson 2000; Slagstad 2003). Unlike the Parry Sound and Britt domains there are no crosscutting mafic dikes in the Shawanaga domain, but there are pods of retrogressed mafic eclogites of uncertain age (unit 54), and 1170 to 1150 Ma coronitic metagabbros (unit 53) (van Breemen and Davidson 1990). The lower boundary of the Shawanaga domain, the Shawanaga shear zone, is a fundamental tectonic feature, straddling the boundary of the monocyclic Shawanaga domain with the polycyclic rocks of the Britt domain. The boundary, which can be precisely located on the islands of Georgian Bay, is the westernmost extension of the Grenville orogen-wide Allochthon Boundary Thrust. Structures related to thrusting are overprinted by extensional (top-to-the-southeast) deformation at circa 1020 Ma (Culshaw et al. 1994; Ketchum et al. 1998) along the Shawanaga shear zone, and the initial thrust sense is indirectly inferred from hanging wall – footwall relationships (e.g., high-pressure rocks are restricted to the hanging wall), although rare thrust-sense kinematic indicators are found inland from Georgian Bay (Culshaw et al. 1989, 1994, 1997). Extension accompanied formation of upright folds, with hinge lines parallel to the southeast-plunging stretching lineation (Culshaw et al. 1994). As with the correlative boundary in between the upper and lower Go Home domains, retrogressed gabbroic eclogite and metre-scale anorthosite blocks are locally associated with the Allochthon Boundary Thrust–Shawanaga shear zone. SAND BAY GNEISS ASSOCIATION The layered rocks of the Sand Bay gneiss association (Culshaw and Dostal 1997) include felsic supracrustal orthogneiss, amphibolite and metasedimentary rocks. Sand Bay metasedimentary rocks include quartzite, calc-silicate and semipelite. The semipelitic Dillon schist is a prominent marker unit that outlines the fold structure of the domain. Early Paleoproterozoic to circa 1400 Ma ages have been recorded from detrital zircons in a Sand Bay gneiss association quartzite (T.E. Krogh, geochronologist, Jack Satterly Geochronology Laboratory, personal communication, 2003). The Dillon schist has yielded zircon grains ranging from 1900±23 Ma to 1362±35 Ma, giving a maximum depositional age for the Sand Bay gneiss association protoliths of circa 1360 Ma (Culshaw and Dostal 1997). The felsic supracrustal orthogneisses are the most voluminous member. These are mostly pink, leucocratic, medium- to finegrained, equigranular migmatitic rocks interpreted as metarhyolites. Grey, more plagioclase-rich intervals are also common. The best exposures of the Sand Bay gneiss association are along the west side of Killbear peninsula (within the provincial park) and on the shoreline of Shawanaga Bay where it is intersected by the syncline cored by Dillon Schist (the type section). A geochemical study of the Sand Bay amphibolites and felsic orthogneisses suggested their protoliths were bimodal volcanic rocks (Culshaw and Dostal 1997; Slagstad 2003). The major and trace element geochemistry of the Sand Bay amphibolites resembles modern continental tholeiites, showing no significant metamorphic disruption of diagnostic trace elements, for example, the high field strength elements (Culshaw and Dostal 1997). The Sand Bay amphibolites have a prominent negative Nb anomaly suggesting involvement of subduction-modified mantle in their genesis. High Th/La in the Sand 9 Bay amphibolites compared to modern mid-ocean ridge basalts (MORB) indicate the possibility of minor crustal contamination. Sand Bay felsic orthogneisses have negative Eu, Ti and Nb anomalies compatible with a continental crustal or arc origin. The igneous protoliths may have originated in a continental environment undergoing active extension, perhaps a continental rift or continental arc-rift (back-arc or intra-arc) setting (Culshaw and Dostal 1997; Slagstad 2003). OJIBWAY GNEISS ASSOCIATION The Ojibway gneiss association is a 1466±11 Ma orthogneiss body of granodioritic-tonalitic composition with arc type granitoid geochemistry (T.E. Krogh, geochronologist, Jack Satterly Geochronology Laboratory, personal communication, 2003). The sheet-like Shawanaga pluton lies along the lower boundary of the Shawanaga domain. It is a circa 1460 Ma body of megacrystic garnet-amphibole-bearing granodiorite-granite (T.E. Krogh, geochronologist, Jack Satterly Geochronology Laboratory, personal communication, 2003). Compositional and age similarities between the Shawanaga pluton, Ojibway gneiss, and grey calc-alkaline gneisses from the Muskoka domain to the south led Slagstad (2003) to suggest that the Shawanaga pluton formed, along with the protoliths to the Ojibway and Muskoka gneiss associations, in a postulated circa 1450 Ma Ojibway–Muskoka arc. The Ojibway–Muskoka arc formed outboard of the Laurentian Britt domain, during the time that the latter underwent back-arc plutonism and 1450 to 1430 Ma granulite facies metamorphism (Ketchum et al. 1998). Upper Go Home Domain (Units 25 to 29) PINE ISLAND GNEISS ASSOCIATION Leucosome-rich granitoid migmatite and pink leucocratic gneiss dominate the upper Go Home domain. Calc-silicate gneiss is a minor component. The upper Go Home domain resembles parts of the Shawanaga domain with respect to its tectonostratigraphic position and composition (e.g., migmatites of the Ojibway gneiss association). The age and details of geochemistry of this domain are unknown. As indicated above, the boundary with the lower Go Home domain is comparable to the lower boundary of the Shawanaga domain. It separates monocyclic from polycyclic rocks and is therefore interpreted to be the Allochthon-Parautochthon boundary thrust; however, unlike the Shawanaga shear zone, it is not overprinted by extensive extensional shear fabrics PERE BREBEUF GNEISS ASSOCIATION This is a unit of apparently uniform grey, migmatitic tonalitic and granodioritic gneiss. Information is scanty, but, on account of its uniformity and lack of associated rocks of definite supracrustal origin, it is interpreted as an orthogneiss of plutonic protolith. It is tentatively distinguished from the adjacent lower Go Home domain on account of lithological differences and because its boundaries, like those of the Pine Island gneiss association, are associated with anorthosite gneiss. Parry Sound Domain (Units 30 to 41) Several thrust-separated, lithologically distinctive subunits with different protolith ages comprise the Parry Sound domain. These are, from north to south, the predominantly supracrustal Lighthouse and Armer Bay gneiss associations which comprise the circa 1400 to 1330 Ma basal Parry Sound domain and 10 the mostly plutonic, circa 1400 to 1200 Ma, interior Parry Sound domain (van Breemen et al. 1986; Wodicka, Parrish and Jamieson 1996). The Parry Sound domain has experienced polyphase Grenvillian metamorphism including pervasive granulite facies metamorphism. An early episode of granulite facies Grenville metamorphism and deformation is recorded at 1160 to 1120 Ma, at least 40 million years before the beginning of any other Grenvillian metamorphism in the remainder of the Central Gneiss Belt (Culshaw et al. 1997). The allochthonous nature of the domain is demonstrated by the presence of granulite facies metamorphic assemblages and the presence of mafic dikes in most rock types, neither of which are present in the underlying Shawanaga or upper Go Home domains (Culshaw et al. 1989, 1997; Wodicka, Parrish and Jamieson 1996). PARRY SOUND DOMAIN (BASAL) The basal Parry Sound domain consists of the Lighthouse and Armer Bay gneiss associations. The Lighthouse gneiss association is thickest in the eastern part of Parry Island and severely thinned in the vicinity of Highway 69. Culshaw and Dostal (2002), working in the vicinity of Bateau Island (the western extremity of its outcrop), showed that the layered metamorphic rocks of the Lighthouse gneiss association, like the subjacent Sand Bay gneiss association, are of volcano-sedimentary origin. On Parry Island the supracrustal members are interlayered with a second grouping of supracrustal rocks (mostly quartzite) and tonalite-granodiorite orthogneiss that are cut by metamorphosed mafic dikes. The diked rocks are thus older than the volcano-sedimentary package and the interlayering of 2 gneiss associations must be tectonic in origin. The volcano-sedimentary Lighthouse gneiss association is dominated by amphibolite and semipelitic to pelitic metasedimentary rocks divided, in the western study area of Culshaw and Dostal (2002), into geochemically and lithologically distinctive upper and lower units. The lower unit amphibolite has a basaltic tholeiite major element composition and a trace element signature resembling oceanic basalt with a minor subduction zone or subduction-modified mantle influence, similar to Sand Bay amphibolite geochemistry (Culshaw and Dostal 2002). The amphibolites of the upper unit have no negative Nb anomaly and have trace element ratios similar to mid-ocean ridge basalt (MORB); therefore, they are likely to have formed from the depleted mantle (Culshaw and Dostal 2002). This evidence and isotopic work in progress suggests the tectonic development of these rocks may be linked to that of both the Shawanaga and the Parry Sound domains. The age of the diked suite is constrained by the 1436±17 Ma age of the youngest detrital zircon in quartzite and the circa 1400 to 1330 Ma age of the orthogneisses (Wodicka, Parrish and Jamieson 1996). It shares detrital ages with parts of the Composite Arc Belt (better known as the Central Metasedimentary Belt; Carr et al. 2000) and the Adirondack Highlands (Wodicka, Parrish and Jamieson 1996). The Lighthouse gneiss association is best observed on the west side of Sandy Island (see Culshaw and Dostal (2002) for location of measured sections). Para-amphibolites (unit 34) are the dominant member of the Armer Bay gneiss association, the thickest member of the basal Parry Sound assemblage on the mainland. It is distinguishable from the Lighthouse gneiss association by differences in the interlayered metasedimentary rocks (generally sulphide bearing in Armer Bay). The geochemistry and geochronology of this unit is unknown, but, on the basis of proximity and physical similarity, it is most likely similar in both aspects to the Lighthouse gneiss association. The contact between the Armer Bay and Lighthouse can be directly observed along the shoreline at Parry Sound where gneissosity in the 2 units is conformable but evidently highly strained. This contact is therefore either primary, tectonic, or both. 11 The circa 1160 Ma (Wodicka, Parrish and Jamieson 1996) Parry Island anorthosite lies within the basal Parry Sound domain on Parry Island, and, presumably, anorthosite that underlies the offshore islands is part of this body. A circa 1350 Ma anorthosite (van Breemen et al. 1986) flanked by a young (lacking mafic dikes) megacrystic granitoid lies within the Armer Bay gneiss association on Parry Island and the mainland. PARRY SOUND DOMAIN (INTERIOR) The interior Parry Sound domain consists of Mesoproterozoic (circa 1400-1200 Ma) granulite facies metaplutonic rocks ranging from gabbro to granite, with subordinate metasedimentary rocks. The most important metaplutonic members appear to be intermediate in composition (spanning granodioritetonalite-quartz diorite). The overall range of orthogneiss compositions, from tonalitic, granitic and granodioritic gneiss to gabbro, suggests a calc-alkaline arc suite. Nd model ages of 1500 to 1400 Ma (Dickin and McNutt 1990) are close to crystallization ages and suggest these rocks formed from a juvenile source. Detailed petrography and geochemistry of these rocks are unknown. Metamorphosed mafic dikes cut all the rocks of the interior, further distinguishing them from rocks of the Shawanaga and upper Go Home domains. The northwestern boundary of the Parry Sound domain interior with the underlying Armer Bay gneiss association is marked for most of its strike length by the Whitestone anorthosite. A northward transect along Highway 69 (or more lightly travelled roads parallel to it) affords a view of the progressive modification of the granulite facies L-S fabric typical of the interior of the domain through a wide zone of retrogression (not shown on maps), to development of linked shear zone systems and penetrative mylonite gneiss close to the boundary. Pegmatite bodies are very common along this transect and appear to be linked to extensional structures that deform the mylonitc fabrics. This boundary is usually viewed as lying within the upper part of the Parry Sound shear zone (PSSZ), which may be thought of as a wide zone of elevated strain extending downward from top of the first shear zones within the interior Parry Sound domain to the top of the Shawanaga domain. Davidson and others (e.g., Davidson, Culshaw and Nadeau 1982; Culshaw, Davidson and Nadeau 1983; Davidson 1984a, 1984b) describe tectonites from several classic localities. This definition of the Parry Sound shear zone requires modification on Parry Island, where there are wide expanses from which the tectonites typical of the Parry Sound shear zone are absent. Moreover, a case can be made that tectonites considered typical of the Parry Sound shear zone are present within the Shawanaga domain well below the rocks normally thought of as lying within the Parry Sound shear zone thus bringing into question the location of a lower boundary to the Parry Sound shear zone. Whether or not the concept of a Parry Sound shear zone in terms of highly strained tectonites is useful as a first order tectonic feature, it seems clear that boundaries between allochthonous units are recognizable and persistent along strike and should be accorded due tectonic significance. The southern boundary of the Parry Sound domain is problematic. This is in part because of uncertainty in precise knowledge of the protoliths at the boundary and in part because of the complex and unusual geometry of the boundaries. For example, there is field evidence that the protolith of parts of the Blackstone Lake gneiss association was a Parry Sound domain lithology. Secondly, the geometry of the boundary, as outlined by the map traces of the anorthosite sheets associated with the Twelve Mile Bay gneiss association and Moon River subdomain, is not easily explained. What can be stated, based on field observation, is that the approach to this boundary from the Parry Sound domain side is accompanied by progressive retrogression of the granulite facies assemblages. In this respect, at least, it resembles the boundary of the Parry Sound domain. 12 Moon River Subdomain (Units 42 to 46) The Moon River subdomain consists of the Twelve Mile Bay, Moon River and Blackstone Lake gneiss associations. These lithological units, together with retrogressed gneisses in the south of the Parry Sound interior (southeast of the retrogression boundary) make up the system of late synforms referred to here as the Moon River structure. It is important to note that this structure consists of more than one lithologically defined domain and therefore postdates thrust stacking of the domains. TWELVE MILE BAY GNEISS ASSOCIATION The Twelve Mile Bay gneiss association (termed assemblage in some older publications) is a thin quartzite, pelite, semipelite and amphibolite unit (unit 44) dominated by 2 extensive sheets of anorthosite gneiss (unit 47) (Culshaw et al.1989). An age of less than 1130 Ma for the quartzite has been suggested based on zircon data (Wodicka, Parrish and Jamieson 1996). At its western end the Twelve Mile Bay gneiss association directly underlies the Parry Sound domain interior and it has been suggested to be physically continuous with the Lighthouse gneiss association of the basal portion of the Parry Sound domain, which it resembles (Culshaw et al. 1989). As indicated above, it has, however, a complex geometry: a lower anorthosite sheet extends southeastward at the contact of the base of the Moon River gneiss association with the Go Home domain. The upper anorthosite, together with the metasedimentary horizons diverges from the lower anorthosite, swinging northwest then northeast around the base of the Moon River gneiss association. This arm of the Twelve Mile Bay gneiss association becomes extremely attenuated (to centimetre thickness) along the northwestern and northeastern contact of the Moon River gneiss association. MOON RIVER GNEISS ASSOCIATION The Moon River gneiss association consists of rocks separated from subjacent units by extensions of the Twelve Mile Bay gneiss association. Prominent among the latter are the persistent horizons of anorthosite gneiss (unit 47). The most important members are uniform pink and grey, generally leucocratic and layered gneisses (unit 45 and 46) in which evidence for plutonic origin, such as deformed megacrysts, is lacking. Minor members include quartzite and para-amphibolite (unit 44). Given the textural nature of the major gneiss members, their similarity with leucocratic gneisses of the Sand Bay gneiss association and their association with minor but definitively metasupracrustal rocks, volcanic protoliths are plausible. However, this cannot be stated with certainty for all members mainly because the gneisses are very structurally evolved. The layered gneissosity that defines the Moon River synform also outlines a refolded nappe (van Berkel and Schwerdtner 1986) and locally can be shown to have been derived by transposition of an older gneissosity. Nd model ages (Dickin and McNutt 1989) demonstrate these rocks are juvenile crust. Small bodies of coronitic gabbro (unit 53) lie along the boundary. BLACKSTONE LAKE GNEISS ASSOCIATION Grey gneisses of granodioritic composition (unit 43b) together with pink leucocratic gneisses (unit 43a), similar to pink gneisses of other domains, are the chief components of the gneiss association. There is local evidence for derivation from Parry Sound rock types but the nature of protolith of the Blackstone Lake gneiss association remains in question. The Blackstone Lake gneiss association has a sheared boundary with local discordance against Parry Sound foliations beneath. A major point of uncertainty is the nature of the relationship of Blackstone rock types with retrogressed Parry Sound gneisses at the 13 southwestern extremity and southern boundary of the gneiss association. These are shown on the maps (P.3550 and P.3551, see back pocket) as sharp boundaries but these boundaries should be viewed with scepticism. DISCUSSION Cross Section of Central Gneiss Belt Along Georgian Bay: from Active Margin to Collisional Orogen The restored cross section of the Central Gneiss Belt (Figure 3) illustrates some aspects of current views of its development. Before the Grenville Orogeny the future thrust sheets of the Central Gneiss Belt were arranged younging oceanward from cratonic Laurentia. The validity of this restoration is supported in that it also places units with similar, but distinctive minor plutonic units (e.g., anorthosite, coronitic gabbro) alongside one another (see Figure 3). Figure 3. Cross section of the Central Gneiss Belt along Georgian Bay. Figure based on geology and seismic reflection profiles; sources can be found in Culshaw et al. (1997). a. postulated arrangement of domains before collision. b. postulated arrangement of domains after collision, convergence and mid-level crustal flow. Abbreviations: lPS, lower Parry Sound domain (now Parry Sound shear zone); GFTZ, Grenville Front tectonic zone; M, Moho; SH, Shawanaga domain; PSD, Parry Sound domain; lGH RA, lower Go Home domain – Rosseau domain; MR–MS, Moon River domain–Muskoka domain; CMBBZ, Central Metasedimentary Belt boundary zone; CMB, Central Metasedimentary Belt; L.GH, lower Go Home domain; U.GH, upper Go Home domain. 14 ACTIVE MARGIN The pre-Grenvillian configuration of the Laurentian margin was arrived at by successive magmatic additions to the periphery of a simple Andean-type margin. At first the arcs, being close to the craton, included considerable volumes of older Laurentian crust. These were later metamorphosed at ~1450 Ma and ultimately became the polycyclic domains of the Grenville Orogen. The proportion of older Laurentian crust diminishes and then vanishes in the younger, more outboard arcs. These are the monocyclic domains. This simple (suspiciously more simple than the Andes!) arrangement of arcs is complicated by the presence within the arcs of rock types indicating intra- or back-arc rifting or distal back-arc bimodal magmatism with significant A-type plutonism. For example, calc-alkaline arc rocks of Shawanaga domain are associated with amphibolites and felsic gneisses of the Sand Bay gneiss association interpreted to represent the magmatic products (basalts and rhyolites, respectively) of rifting of the same arc. Another example is given by the ~1450 Ma plutons of the Britt domain (e.g., Britt pluton) that are interpreted to have been emplaced far behind the active arc into an older arc. As these examples suggest, further complications to the simple oceanward-younging hypothesis will probably emerge as a result of future studies. COLLISIONAL OROGEN In the current model, the present configuration of the Central Gneiss Belt was derived from the oceanward-younging version of the Laurentian margin by classic forward-propagating thrusting with minimum out-of-sequence thrusting in combination with pervasive ductile flow. Although, the case for thrust-stacking can be made on the basis of lithostratigraphy alone, it has also been argued that most of the boundaries of the domains are discrete thrust-sense shear zones. They may have high-strain structures such as sheath folds, a variety of kinematic indicators and, in some cases, boundaries of overlying units truncating structures below. However, a simple model based on foreland fold-and-thrust belts is clearly inappropriate. This is because most of the thrust-stacked domains, unlike high-level thrust sheets, consist of planar bodies of gneiss formed during one or more episodes of ductile flow that affected entire thrust sheets (Culshaw et al. 1997). The gneiss within the thrust sheet may comprise layered straight gneiss (often migmatitic) or leucosome-rich migmatite with a well-developed planar fabric and a variety of high-strain features (e.g., isoclinal folds). The elevated level of ductile deformation required to make such straight gneiss is demonstrated locally where strain gradients preserve different stages of its formation from original, sometimes irregularly shaped, compositional heterogeneities. Repetition of this level of deformation is shown where straight gneiss is transposed a second time (kneading) or folded by domain-scale nappes that are, in turn, refolded. That the conditions appropriate for such ductile flow persisted over a considerable period is shown by widespread upper amphibolite to granulite facies conditions and generation of migmatite and U/Pb ages that suggest high-grade metamorphism was attained more or less continuously for about 50 million years. Having established that thrust stacking and pervasive ductile flow of the thrust stack both took place, the question of the relative timing and nature of the relationship of the 2 phenomena remains. Did they occur simultaneously or were they separated in time? 15 Economic Geology OVERVIEW Little modern mineral exploration has been conducted within the Central Gniess Belt, in part because of the perception that high-grade gneiss terranes have little mineral potential. Lack of detailed geologic maps and mineral deposit models have also discouraged mineral exploration. Nevertheless, our understanding of the tectonic architecture of the region allows establishment of a broad framework for mineral exploration within the Central Gneiss Belt (see also Easton and Fyon 1992). For example, flagstone is a major commodity that is not domain specific, as the best flagstone prospects are found in transposed and straight gneiss zones associated with terrane or domain boundaries. Also associated with terrane or domain boundaries are circa 1170 million-year-old mafic and ultramafic bodies (metabasites and pseudoecologites) which have recently been explored for platinum group element, copper and gold mineralization (Garland and Villard 1990). MINERAL OCCURRENCES Maps P.3548 to P.3552 (see back pocket) include all known metallic and nonmetallic Mineral Deposit Inventory (MDI) occurrences within the study area. Examination of specific mineral occurrences and prospects was not a focus of the study or the mapping program. With few exceptions, the MDI occurrences are localized into 5 geographic groups. 1. Occurrences near Britt Station (see Map P.3548) associated with pegmatite veins in or adjacent to the Still River gneiss association (unit 5). These occurrences have been examined for feldspar, uranium, rare elements, and columbite. To date, no significant mineralization has been found. 2. Occurrences located within the interior of Parry Sound domain (see Maps P.3550 and P.3551). Villard, Keevil and Hogg (1984) summarized these occurrences, many of which may contain minor amounts of gold. Most are associated with quartz veins, and contain varied amounts of chalcopyrite, pyrite and pyrrhotite, which are generally the minerals reported in MDI. The veins are spatially associated with metamorphosed quartz diorite bodies surrounded by mafic gneisses. 3. Occurrences of flagstone producing and past-producing quarries in the Parry Sound shear zone (see Map. P.3350). Marmont (1991) summarized the flagstone potential within the western Central Gneiss Belt of Ontario. 4. Occurrences located east of Blackstone Lake and near Mactier (see Map. P.3551) are associated with pegmatite veins hosted by leucogneiss (unit 43) of the Blackstone Lake gneiss association, in close proximity to mafic rocks of the anorthosite suite (unit 47). These occurrences were examined for feldspar, uranium, rare elements, and columbite between 1910 and 1925 (Hewitt 1967). To date, no significant mineralization has been found. Proximity to the Canadian Pacific railway right-of-way was probably a major factor in the initial examination of these occurrences. 5. Occurrences in the vicinity of Six Mile Lake Provincial Park (see Map P.3552) that are associated with rusty schists and marble horizons in the Honey Harbour gneiss association of the lower Go Home domain. Mineralization consists of graphite and minor gold and sulphide occurrences. Easton (1995) describes these occurrences, including several not included within MDI. 16 MINERAL POTENTIAL Parautochthon Few mineral occurrences have been reported from rocks of the parautochthon. The polycyclic character of the rocks present in the parautochthon, in conjunction with the abundance of felsic, moncyclic plutonic rocks, suggests that this part of the study area has limited mineral potential. The exception to this assessment may be the metasedimentary rocks of the lower Go Home domain, which host minor graphite, gold and sulphide occurrences (Easton 1995). Allochthon Apart from the Parry Sound domain, which is described below, few mineral occurrences have been reported from rocks of the allochthon. The presence of metasedimentary rocks within much of Shawanaga domain, as well as the presence of both mafic and felsic metavolcanic rocks of continental affinity in this domain (Culshaw and Dostal 1997, 2002) suggest that Shawanga domain might have a higher mineral potential than previously thought. Commodities of interest are volcanogenic massive sulphide deposits (VMS) and sedimentary-hosted (SEDEX) base metal deposits. PARRY SOUND DOMAIN The abundance of mafic rocks and carbonate and pelitic gneisses in the Parry Sound domain makes this region the most extensively prospected and the best exploration target in the Central Gneiss Belt. Villard, Keevil and Hogg (1984) summarized the numerous gold prospects in the area. Most are associated with quartz veins, and contain associated chalcopyrite, pyrite and pyrrhotite, and are spatially associated with metamorphosed quartz diorite bodies surrounded by mafic gneisses. Two vein types are documented: (1) copper-gold-bearing veins in gabbroic rocks in mafic gneiss; and (2) copper-nickel- and copper-zincbearing veins in the contact zone between felsic and mafic gneiss. Minor past production was achieved from a few deposits (Satterly 1943; Garland and Villard 1990). Northeast of the study area, small bodies of massive magnetite occur in Lount Township within garnet-hornblende gneiss and may represent disaggregated or disrupted iron formation (Easton and Fyon 1992). The industrial mineral potential of the Parry Sound domain is high, and includes alumina sources (mainly meta-anorthosite; Marmont 1988a), agricultural lime from marbles (Marmont 1988b), building stone (Marmont 1991) and flagstone (Fouts and Marmont 1989). The best flagstone quarries are located in the Parry Sound shear zone. References Adams, F.D. and Barlow, A.E. 1910. Geology of the Haliburton and Bancroft area, Province of Ontario; Geological Survey of Canada, Memoir 6, 419p. 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Metamorphism 1700±100 m.y. and 900±100 m.y. ago in the northwest part of the Grenville Province in Ontario; Carnegie Institution of Washington, Yearbook 68, p.308-309. Krogh, T.E. and Davis, G.L. 1970b. Isotopic ages along the Grenville Front in Ontario; Carnegie Institution of Washington, Yearbook 68, p.309-313. Krogh, T.E. and Davis, G.L. 1971. Paragneiss studies in the Georgian Bay area 90 km southeast of the Grenville Front; Carnegie Institution of Washington, Yearbook 69, p.339-341. Logan, W.M. 1863. Report on the geology of Canada; Geological Survey of Canada, Report of Progress from its Commencement to 1863, 963p. Logan, W.M. 1866. Report of progress 1863-1866; Geological Survey of Canada, p.93. 20 Lowdon, J.A. 1960. Age determinations by the Geological Survey of Canada, Report 1: Isotopic Ages; Geological Survey of Canada Paper 60-17, 51p. Lowdon, J.A. 1961. 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Comment 31D13, Penetanguishene z U 1047 2 Bussy et al. 1995 z U 1469 11 Ketchum and Krogh 1997 Go Home domain, pseudoeclogite, upper intercept, crystallization age #4, Go home domain, age of regional metamorphism z U 1089 2 Ketchum and Krogh 1997 Go Home domain, pseudoeclogite, lower intercept, metamorphic age 31E4, Lake St. Joseph 984 976 985 995 940 976 761 839 860 Blackstone Lake, 207Pb/206Pb near concordant minimum Blackstone Lake, 07Pb/206Pb , minimum Blackstone Lake GSC 59-45 GSC 59-44 Conger Twp, 07Pb/206Pb near concordant minimum Tor 1223A Tor 1224A PS86B-1B, plateau age u u k m m u k b m W W K K K W K K A z z U U 1300 +17/-25 Wodicka, Parrish and Jamieson 1996 1317 24 Wodicka, Parrish and Jamieson 1996 90N213, tonalite, Paleoproterozoic inheritance at ~1660 and ~2270Ma 90N202, tonalite, interior Parry Sound domain, same age as the McKellar gneiss (1326 as recalculated from van Breemen et al. 1986) z z U U 1163 1151 3 Wodicka, Parrish and Jamieson 1996 1 Wodicka, Parrish and Jamieson 1996 90N210, crystallization age, Parry Island anorthosite 89N153c, dike cutting Parry Island anorthosite, minimum age of crystallization and time of metamorphism z U <1121 z z w z z U U R U U 1350 1346 1330 1159 1377 4 Wodicka, Parrish and Jamieson 1996 41H7 and 41H8, Parry Sound 50 van Breemen et al. 1986 +69/-39 van Breemen et al. 1986 44 Connare & McNutt 1985 +5/-4 van Breemen et al. 1986 14 Wodicka, Parrish and Jamieson 1996 z z U U 1160 1382 Circa Wodicka, Parrish and Jamieson 1996 30 Wodicka, Parrish and Jamieson 1996 w z R U 1145 1042 Krogh and Davis 1969 4 Ketchum et al. 1998 #13, n=2 91-270, pre-kinematic dike cutting Pointe-au-Baril complex, in Shawanaga shear zone z U 1019 4 Ketchum et al. 1998 z U 988 2 Ketchum et al. 1998 t t t t t m b m m m U U U U U A A A A A 1045 1026 967 956 1058 897 926 894 889 903 Ketchum et al. 1998 Ketchum et al. 1998 Ketchum et al. 1998 Ketchum et al. 1998 Tuccillo et al. 1992 Cosca 1989 Cosca 1989 Cosca 1989 Cosca 1989 Cosca 1989 91-267a, late syn-kinematic dike cutting Pointe-au-Baril complex, in Shawanaga shear zone 91-269, post-kinematic dike cutting Pointe-au-Baril complex, in Shawanaga shear zone LH89-11-2, 07Pb/206Pb age LH89-11-1, 07Pb/206Pb age DS-1-2, 07Pb/206Pb age DS-1-1, 07Pb/206Pb age 91-16 PSA-1, plateau PSA-2, plateau PS86B-9, plateau PS86B-14B, plateau PS86B-16C, plateau 40 60 60 70 80 3 2 4 4 3 3 3 Stockwell 1982 Wasserburg & Hayden 1955 Wasserburg and Hayden 1955 Lowdon 1960 Lowdon 1960 Cumming et al. 1955 Cumming et al. 1955 Cumming et al. 1955 Cosca 1989 41H1, Sans Souci 90N205c, 12 Mile Bay quartzite, youngest single grain Whitestone anorthosite near Mill Lake, Geology of Ontario #321 Nobel gneiss (marginal orthogneiss), Geology of Ontario #323 Nobel gneiss, n=?, Isr=0.7033/17, MSWD=1.67 1159+5/-4, syntectonic pegmatite, Parry Sound shear zone Isabella Island granite gneiss, cuts Whitestone anorthosite, upper limit for igneous crystallization 89N104, Isabella Island granite gneiss, time of regional metamorphism 88N36c, megacrystic granite, best estimate of emplacement age, mimimum age of 1361+/-9 Ma, metamorphism at 1160 Ma 24 Reference Error, in Ma Age, in Ma Decay System Mineral Appendix 1. Listing of published geochronological data for the study area - continued. 3 2 5 5 3 8 6 10 8 12 Comment 41H7 and 41H8, Parry Sound Cosca 1989 Cosca 1989 Culshaw, Reynolds and Check 1991 Culshaw, Reynolds and Check 1991 Culshaw, Reynolds and Check 1991 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Ketchum and Krogh 1997 m b h b m m m m m z A A A A A A A A A U 909 1126 969 943 905 888 899 884 891 1121 z U 1001 z z z z U U U U 1095 1091 1114 <1385 w z t R U U 1752 1457 1430 t t U U 998 1049 15 Ketchum et al. 1998 Ketchum et al. 1998 t t t t t t t t t t t t t z U U U U U U U U U U U U U U 985 961 1028 1024 1005 1004 1000 1000 958 1022 1018 1008 966 1452 Ketchum et al. 1998 Ketchum et al. 1998 Ketchum et al. 1998 Ketchum et al. 1998 Ketchum et al. 1998 Ketchum et al. 1998 Ketchum et al. 1998 Ketchum et al. 1998 Ketchum et al. 1998 Ketchum et al. 1998 Ketchum et al. 1998 Ketchum et al. 1998 Ketchum et al. 1998 2 Ketchum et al. 1994 z U 1448 1 Ketchum et al. 1994 t g g m m a a h U U U U U U U A 1078 1123 1396 1053 1062 1435 1450 974 4 3 6 2 2 2 1 5 PSI-861, plateau PSI-861, total gas, excess argon, in Parry Sound shear zone #6 #6 #7 #10 #11 #12 #13 Frederic Inlet pseudoecologite, Twin Doves Island, upper intercept, metamorphic age Frederic Inlet pseudoecologite, Twin Doves Island, lower intercept, metamorphic age Frederic Inlet pseudoecologite, Hooper Island, metamorphic age Frederic Inlet pseudoecologite, King Bay, metamorphic age #1, dike cuts early metamorphic fabric in Parry Sound domain 88N39b, Parry Sound assemblage quartzite, youngest grain, maximum age of deposition 4 Ketchum and Krogh 1997 Ketchum and Krogh 1997 11 Ketchum and Krogh 1997 2 Bussy et al. 1995 4 Wodicka, Parrish and Jamieson 1996 41H9 and 41H10, Naiscoot 95 Krogh & Davis 1969, 1970a, 1970b, 1971b Pointe-au-Baril, #11, n=10, Isr=0.7016 +8/-6 van Breemen et al. 1986 Britt pluton emplacement, Geology of Ontario #320 17 Ketchum et al. 1998 GC89-117, tonalite phase of Pointe-au-Baril complex, upper intercept GC89-117, tonalite phase of Pointe-au-Baril complex, lower intercept TK84-92-1, 07Pb/206Pb, also 985 & 961 Ma fractions, older metamorphism TK84-92-1, 07Pb/206Pb age TK84-92-1, 07Pb/206Pb age GC89-128-1, 07Pb/206Pb age GC89-119-2, 07Pb/206Pb age GC89-119-1, 07Pb/206Pb age GC89-118-1, 07Pb/206Pb age GC89-118-1, 07Pb/206Pb age GC89-122-1, 07Pb/206Pb age GC89-123-1, 07Pb/206Pb age GC89-124-1, 07Pb/206Pb age DS-3-1, 07Pb/206Pb age DS-4-1, 07Pb/206Pb age GC89-127-1, 07Pb/206Pb age 89-37a, mafic granulite, dates granulite facies metamorphism in Britt domain 91-266, leucosome in mafic granulite, dates granulite facies metamorphism in Britt domain at 1448 to 1452 Ma Tuccillo et al. 1992 Tuccillo et al. 1992 Tuccillo et al. 1992 Tuccillo et al. 1992 Tuccillo et al. 1992 Tuccillo et al. 1992 Tuccillo et al. 1992 Culshaw, Reynolds and Check 1991 91-18, in Parry Sound shear zone PS88-1, garnet, in Parry Sound shear zone SH88-7b, garnet, Britt domain SH88-7b/1, Britt domain SH88-7b/2, Britt domain SH88-58/1a, allanite, Britt domain SH88-58/2a, allanite, Britt domain #4, Britt pluton 25 964 948 904 904 899 896 1152 1050 Error, in Ma Age, in Ma Decay System Mineral Appendix 1. Listing of published geochronological data for the study area - continued. 5 5 3 6 6 6 2 Reference Comment 41H9 and 41H10, Naiscoot Culshaw, Reynolds and Check 1991 Culshaw, Reynolds and Check 1991 Culshaw, Reynolds and Check 1991 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Heaman and LeCheminant 1993 Heaman and LeCheminant 1993 #5, Shawanaga pluton #5, Shawanaga pluton #5, Shawanaga pluton #50 #60 #70 coronitic metagabbro, see also van Breemen and Davidson 1990 coronitic metagabbro, see also van Breemen and Davidson 1990 h b m m m m d z A A A A A A U U z U * 1460 +12/-8 Krogh (unpubublished) cited in Ketchum et al. 1998 Pointe-au-Baril complex granite, no location specified z U * 1457 +10/-11 Ketchum et al. 1998 inherited zircon in pegmatite (GC91-267a,GC91-269,GC91-270) cutting Pointe-au-Baril complex, upper intercept, no single location z U * ~1063 z U u u d W W U z z z z z t n z t t t U U U U U U U U U U U 1013 2 Davidson & van Breemen 2001 1684 8 Corrigan, Culshaw and Mortensen 1994 1146 +137/-128 Corrigan, Culshaw and Mortensen 1994 1442 +7/-6 Corrigan, Culshaw and Mortensen 1994 945 +47/-48 Corrigan, Culshaw and Mortensen 1994 972 7 Corrigan, Culshaw and Mortensen 1994 1035 1 Corrigan, Culshaw and Mortensen 1994 1456 12 Corrigan, Culshaw and Mortensen 1994 1015 16 Corrigan, Culshaw and Mortensen 1994 990 2 Corrigan, Culshaw and Mortensen 1994 ~980 Corrigan, Culshaw and Mortensen 1994 87DM34, zircon fraction, 07Pb/206Pb age #1, upper intercept, Key Harbour granite #1, lower intercept, Key Harbour granite #2, upper intercept, Mann Island granodiorite #2, lower intercept, Mann Island granodiorite #2, Mann Island granodiorite, 07Pb/206Pb age #3, peak M3 metamorphism, cooling through 725°C #4, upper intercept, time of leucosome formation #4, lower intercept, time of post-metamorphic cooling #5, age of dike emplacement #6, granodiorite similar to Mann Island granodiorite, similar titanite age to Mann Island granodiorite h b m k b m h b h k h k h k m h A A A A A A A A A A A A A A A A 968 978 924 902 993 922 967 1004 1020 917 991 980 992 936 931 1005 #1, Britt pluton #1, Britt pluton #1, Britt pluton #1, Britt pluton #2, Britt pluton #2, Britt pluton #3, Britt pluton #3, Britt pluton, excess argon? #102, plateau, eastern Grenville Front tectonic zone #102, plateau, eastern Grenville Front tectonic zone #103, plateau, eastern Grenville Front tectonic zone #103, plateau, eastern Grenville Front tectonic zone #33, plateau, eastern Grenville Front tectonic zone #33, plateau, eastern Grenville Front tectonic zone #38, plateau #118, plateau Ketchum et al. 1998 Near concordant overgrowths on inherited zircons in pegmatite, dates regional metamorphism, no single location 41H15, Key Harbour 1467 +11/-7 Davidson and van Breemen 1994 1043 875 >1454 Kings Island pluton, near Grenville Front tectonic zone--Britt domain boundary, similar age to Britt pluton Besner Mine, 207Pb/206Pb near concordant minimum Besner Mine, 207Pb/206Pb near concordant maximum 87DM34, 3 discordant grains yield minimum age, 07Pb/206Pb ages of 1287, 1343 and 1454 Ma Lowdon 1961 Cumming et al. 1955 Davidson and van Breemen 2001 5 6 3 6 5 3 7 6 5 8 5 8 8 8 7 8 Culshaw, Reynolds and Check 1991 Culshaw, Reynolds and Check 1991 Culshaw, Reynolds and Check 1991 Culshaw, Reynolds and Check 1991 Culshaw, Reynolds and Check 1991 Culshaw, Reynolds and Check 1991 Culshaw, Reynolds and Check 1991 Culshaw, Reynolds and Check 1991 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 26 k h m k h m m m k b A A A A A A A A K K 929 998 934 922 990 932 903 904 835 779 Error, in Ma Age, in Ma Decay System Mineral Appendix 1. Listing of published geochronological data for the study area - continued. 8 7 8 5 7 9 8 50 50 Reference Comment 41H9 and 41H10, Naiscoot Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Reynolds et al. 1995 Lowdon 1960, 1961 Lowdon 1960, 1961 #118 #49 #49 #49 #107 #108 #1a #40 GSC 59-47 GSC 59-46 Mineral abbreviations: a = allanite, b = biotite, d = baddeleyite, g = garnet, h = hornblende, k = potassium feldspar, m = muscovite, n = monazite, t = titanite, u = uranitinite, w = whole rock, z = zircon. Decay system abbreviations: A = 40Ar/39Ar , K = K/Ar, R = Rb/Sr, U = U/Pb, W = Pb/Pb. All ages are plotted on maps P.3548 through P.3552, except for ages with an * appearing before the age. In these cases, no specific location was available, or the ages reported are composites from several sample sites. 27 Metric Conversion Table Conversion from SI to Imperial Conversion from Imperial to SI SI Unit Multiplied by Gives Imperial Unit 1 mm 1 cm 1m 1m 1 km 0.039 37 0.393 70 3.280 84 0.049 709 0.621 371 LENGTH inches 1 inch 25.4 inches 1 inch 2.54 feet 1 foot 0.304 8 chains 1 chain 20.116 8 miles (statute) 1 mile (statute) 1.609 344 mm cm m m km 1 cm@ 1 m@ 1 km@ 1 ha 0.155 0 10.763 9 0.386 10 2.471 054 AREA square inches 1 square inch square feet 1 square foot square miles 1 square mile acres 1 acre 6.451 6 0.092 903 04 2.589 988 0.404 685 6 cm@ m@ km@ ha 1 cm# 1 m# 1 m# 0.061 023 35.314 7 1.307 951 VOLUME cubic inches 1 cubic inch cubic feet 1 cubic foot cubic yards 1 cubic yard 16.387 064 0.028 316 85 0.764 554 86 cm# m# m# CAPACITY 1 pint 1 quart 1 gallon Multiplied by 1L 1L 1L 1.759 755 0.879 877 0.219 969 pints quarts gallons 1g 1g 1 kg 1 kg 1t 1 kg 1t 0.035 273 962 0.032 150 747 2.204 622 6 0.001 102 3 1.102 311 3 0.000 984 21 0.984 206 5 MASS ounces (avdp) 1 ounce (avdp) 28.349 523 ounces (troy) 1 ounce (troy) 31.103 476 8 pounds (avdp) 1 pound (avdp) 0.453 592 37 tons (short) 1 ton (short) 907.184 74 tons (short) 1 ton (short) 0.907 184 74 tons (long) 1 ton (long) 1016.046 908 8 tons (long) 1 ton (long) 1.016 046 90 1 g/t 0.029 166 6 1 g/t 0.583 333 33 CONCENTRATION ounce (troy)/ 1 ounce (troy)/ ton (short) ton (short) pennyweights/ 1 pennyweight/ ton (short) ton (short) Gives 0.568 261 1.136 522 4.546 090 L L L g g kg kg t kg t 34.285 714 2 g/t 1.714 285 7 g/t OTHER USEFUL CONVERSION FACTORS 1 ounce (troy) per ton (short) 1 gram per ton (short) 1 ounce (troy) per ton (short) 1 pennyweight per ton (short) Multiplied by 31.103 477 grams per ton (short) 0.032 151 ounces (troy) per ton (short) 20.0 pennyweights per ton (short) 0.05 ounces (troy) per ton (short) Note: Conversion factors which are in bold type are exact. The conversion factors have been taken from or have been derived from factors given in the Metric Practice Guide for the Canadian Mining and Metallurgical Industries, published by the Mining Association of Canada in co-operation with the Coal Association of Canada. 28 ISSN 0826--9580 ISBN 0--7794--6720--5 LEGEND 79°39´55 45´ 50´ 55´ 80°00´00 81 580000m 79 84 83 82 60 29a 18b 4983000m Big Splitrock 50b 35 Island Island 33 Rabbit 45 35 37 45 85 Home 70 Bay Long Island 48b 51a 50b 82 QUATERNARY 4983000m Sahanatien 15b Lake St. Patrick er iv R 65 50b Landing GIBSON I.R. 31 18a 57 and till 33 2 4980000m ua 30 32 a qu us M 50b 84 18b 30 r 65 50b 60 82 51a 48b 30 12 20 Island 29b 28 Island 20 5 29b 70 68 Cognashene 10 28 34 Maxwell 75 Island Island 25 Island 13 35 66 35 18b 50b 50 20 35 35 20 29a 80 55´ Whalesback 30 74 Islands 48b 40 65 29b Tomb Island Island 29b 16 23 PARK 20 25 Minnicog- 29a 40 30 8 70 Island 51 72 60 18b 35 80 20 50 4 20 18b 53 75 25 3 30 15b 5 32 34 40 15 CONGER TP 20 71 80 50 Point 48 5 Roberts Island 4970000m Ti 52 il Isla nd Kettle's Bay Sawlog Bay Clearwater Beach Kettle's Beach 18b Gignac Lake 76 70 54b 23 45 6 85 48a 18b 6 66 86 67 57 25 40 20 25 20 15b 18b 18b 10 17 14 22 Kettle's P 's tt e 56 14 Cr Marygrove 23 10 INTRUSIVE CONTACT 25 26 25 10 10 25 20 6 18b r u Black Bay Lake 10 80 St gr 25 C r eek Beach 56 Lake 42 Port Severn 45 Amphibolite 44c Interlayered amphibolite, semi-pelitic gneiss and 17b 41 47a 43 25 40 4960000m Green 60 47a 4 TAY TP W a 39 Midland Point u sh e Portage Park Sunnyside e C 56 ha nn 15b Marble; may be associated with rusty graphitic schist 15c Calc-silicate gneiss Migmatitic Rocks Pink, sugary, layered leucocratic gneiss of granodioritic to monzodioritic composition 43b Grey biotite leucogneiss of granodioritic composition Migmatitic Rocks Mafic Rocks Grey, leucocratic, migmatitic hornblende-biotite-garnet Amphibolite orthogneiss of tonalitic to granodioritic composition 12 Metasedimentary Rocks Unclassified paragneiss 11 Metasedimentary Rocks Pink, layered, leucocratic paragneiss Felsic Rocks 10 Metasedimentary Rocks Rusty weathering, graphitic paragneiss Intermediate to Felsic Granulites Unsubdivided, grey to buff weathering, orthopyroxene- 9 Metasedimentary Rocks bearing intermediate (granodiorite, tonalite to diorite) Grey, migmatitic, leucocratic garnet-biotite paragneiss, orthogneiss locally with sillimanite; pink leucosome, may contain garnet, Intermediate to Felsic Granulites (layered) Bayfield Gneiss Association (units 6 to 8) Intermediate to Felsic Rocks Pink, sugary leucocratic gneiss Intermediate to Felsic Granulites (retrogressed) Unsubdivided, grey, foliated to gneissic, intermediate 7 Intermediate to Felsic Intrusive Rocks 7a evidence of retrogression from a granulite facies precursor 58 potassium feldspar megacrysts 37 Sunset Beach 7b Mafic Rocks granulite or gneissic metagabbro H o g Ba y TAY TP 6 TAY TP 36 ls Stur geon Bay 4957000m Crystal Beach Metasedimentary Rocks 36a Layered paragneiss, garnet-rich granulite 36b Marble, calc-silicate tectonic breccia Metasedimentary Rocks 6a 17b 56 rusty weathering ls PROVINCIAL PARK 44°45´00 93 580000m 80°00´00 56 81 82 83 84 86 85 55´ 87 88 89 590000m 91 93 92 50´ 94 95 96 97 98 99 45´ 600000m 01 02 03 604000m Calc-silicate and amphibolite gneiss associated with garnet-biotite paragneiss of unit 6a Matchedash Bay WAUBASHENE BEACHES Ogden's Beach Grey, leuco- to mesocratic garnet-biotite paragneiss, commonly with sillimanite; locally graphitic and 6b 44°45´00 Grey, leucocratic, migmatitic hornblende-biotite-garnet orthogneiss of tonalitic to granodioritic composition Unsubdivided, layered, predominantly mafic two-pyroxene 17b 4956000m Unsubdivided grey and pink, variably layered, highly strained orthogneiss, in places with recrystallized (e.g., unit 39 or 40); pegmatite veins may be common Triple Bay Park 57 Synform, interpreted; unknown generation, trend only, limbs dip Lineation (with plunge, in opposite directions subhorizontal) 35 Mineral occurrences, Fold axis; minor fold, prospects, m-asymmetry discretionary (with plunge) occurrences (as classed by the Geological contact Mineral Deposit (interpreted) Inventory (MDI)) Limit of mapping; Location of isotopic denotes limits of area mapped during this survey Fault, interpreted; trend only bA 978 ± 6 age determination Dorset 117 Sans Souci Dyer's Bay Baysville MacTier P.3551 (trend only, inclined) 35 Port Sydney 141 BAY Tobermory Dwight 60 Huntsville Rosseau 6 Foliation 11 Orrville Parry Sound 118 400 Bala Lion's 118 Bracebridge 169 45° Head 45° Edenhurst Honey Harbour Purple Valley LAKE Penetanguishene Gravenhurst P.3552 Norland Washago 12 Wiarton HURON 81° Shallow Nottawasaga Midland Bay Leith 26 Woodford 11 80° Thornbury Location Map 12 169 79° Orillia 48 427m Brechin 1 cm equals 25 km SOURCES OF INFORMATION Thematic information on this map is tied to a digital base map derived from map 31 D/13 of the National Topographic System, scale 1:50 000. American Datum 1983 (NAD83), Zone 17. Geological Survey of Canada Ontario Department of Mines 1954. Aeromagnetics, Penetanguishene; Geological Survey of Canada Ontario Department of Mines, Geophysical Map 128G, scale 1:63 360. ABBREVIATIONS Ontario Geological Survey 2002. (MDI2) gf ............................................................graphite ls ..........................................................limestone St gn...............................................stone, gneiss St gr...............................................stone, granite Ti ............................................................titanium zU = zircon U/Pb date, in Ma Mineral Deposit Inventory Version 2 October 2002 Release; Ontario Geological Survey, Digital Data. Bussy, F., Krogh, T.E., Klemens, W.P. and Schwerdtner, W.M. 1995. Tectonic and metamorphic events in the westernmost Grenville Province, central Ontario: new results from high-precision U-Pb zircon geochronology; Canadian Journal of Earth Sciences, v.32, p.660-671. Culshaw, N.G., Corrigan, D., Drage, J. and Wallace, P. 1988. Georgian Bay geological synthesis: Key Harbour to Dillon, Grenville Province of Ontario; in Current Research, Part C, Geological Survey of Canada, Paper 88-1C, p.129-133. Ketchum, J.W.F. and Krogh, T.E. 1997. U-Pb constraints on high- Grenville orogen; Geological Association of Canada Mineralogical Association of Canada, Programs with Abstracts, v.22, p.A-78. 1 foot = 0.3048 m. 05 79°39´55 CREDITS N. Wodicka, 1987 to 1990. Geological compilation by N.G. Culshaw, 1991 and 2004. Digital drafting by S. Josey. R.M. Easton. Unclassified paragneiss 43a (granodiorite, tonalite to diorite) orthogneiss containing 17b el Robin's Point Island Grandview Beach in opposite directions Broadbent Nobel P.3550 Mafic orthogneiss Britt Domain (units 1 to 14) 8 38 Methodist 58 Midl and Bay n Mafic Rocks granulite 59 Canary Island a Monzonitic to granitic orthogneiss PARAUTOCHTHON NORTH OF PARRY SOUND DOMAIN Unsubdivided, buff to grey weathering, layered, feldspathic Forest Harbour u b 17b muscovite, magnetite 17b 17b Paradise Point trend only, limbs dip vertical) GEORGIAN Novar Cartographic production by S. MacLean. received a technical edit. Discrepancies may occur for which the Ontario Ministry of Northern Development and Mines does not assume 18b 22 Penetang 69 Kearney Sprucedale McKellar To enable the rapid dissemination of information, this map has not Island 18b 59 Unclassified granitoid orthogneiss Grey, migmatitic, leucocratic hornblende-biotite orthogneiss Buff to pink weathering, leucocratic granulite Island 20 TAY TP 17a Intermediate to Felsic Rocks Parry Sound Domain (interior) (units 36 to 41) Potato 18b Intermediate to Felsic Rocks 15a PARRY SOUND DOMAIN (INTERIOR) 25 35 Pink to grey, migmatitic leucogranite to granodiorite Quartzite 18b St. Andrews Penetanguishene Mafic orthogneiss 44b TECTONIC CONTACT WITH SUBJACENT 61 60 Point 44a Channel 32 Pink to grey leucocratic gneiss 18b BASE OF LOWER GO HOME DOMAIN NOT OBSERVED Mafic and Metasedimentary Rocks Tug Lake Pointe au Geology, legend and mineral deposit information reviewed by 13 St gr 15 18a Metasedimentary Rocks 15 Intermediate to Felsic Rocks 62 26 6 Pen e Cranberry St gr 36 30 tan g Ha rbour 43 15 25 26 27 10 Dunchurch Geology by N.G. Culshaw, D. Corrigan, J.W.F. Ketchum, P. Wallace and 14 30 61 (trend only, inclined, 35 Ardbeg Baril Station Felsic Rocks 18 Blackstone Lake Gneiss Association (units 42 and 43) 45 42 18b 17b Reynolds Grey, migmatitic layered gneiss 15 45 47a unknown generation, Magnetawan Burk's Falls P.3549 Metric conversion factor: Nadeau Island Gneiss Association (units 9 to 14) 25 35 18b Su ck er Petaguishene Antiform, interpreted; unknown generation 35 Ahmic Harbour Inlet Honey Harbour Gneiss Association (units 15 to 18) 63 Little Lake 15 zU 1469 ± 11 62 Pink, sugary, layered leucocratic gneiss 46b quartzite 55 60 32 Lake 46a 35 20 Point foliation; South River Sundridge Magnetawan Geology not tied to surveyed lines. Felsic to Intermediate, Layered or Migmatitic Rocks 44d Moore zU 1089 ± 2 Point 44 Point 53 Basin Highland 64 30 60 Peekaboo Point Port Loring North Magnetic declination approximately 10°49'W in 2004. Grey, migmatitic tonalite to granodiorite orthogneiss 35 53 Farlain 4960000m e 18 35 Northwest Toanche 47a 80 Present Island 53 Farlain L ak 10 St gr a rb o r 46 65 's Leduc 65 H Pakesley PARAUTOCHTHON SOUTH OF PARRY SOUND DOMAIN 18b 17a te u 50´ 33 64 Key Commanda ALLOCHTHON-PARAUTOCHTHON BOUNDARY Moon River Gneiss Association (units 44 to 46) 45 32 46° Restoule Pickerel pressure metamorphism in the Central Gneiss Belt, southwestern 24 Point O ro n 14 Beausoleil 18b 6 Grey hornblende-epidote-biotite tonalitic orthogneiss (NADEAU ISLAND GNEISS ASSOCIATION): Moon River Subdomain (units 42 to 46) 13 Grey, migmatitic, tonalitic to granodioritic gneiss with TECTONIC CONTACT WITH SUBJACENT BRITT DOMAIN 16 14 10 Fossmill varied amounts of pink leucosome 17 8 14 20 Coutnac Beach 20 Grey metatextite with pink, hornblende-epidote-bearing ALLOCHTHON 66 73 Maceys Bay 23 25 Kiosk 79° Powassan LATE PALEOPROTEROZOIC 69 r a 65 50´ TINY TP 400 17 B 56 Migmatitic Rocks 19b 17 12 Intermediate to Felsic Rocks leucosome EARLY MESOPROTEROZOIC to 19 10 23 ee k PROVINCIAL PARK 63 67 46 30 18 Quartzite 19a 50 12 10 10 22 21e Small outcrops of unit 47a or 47b hosted by adjacent 80 37 5 80 80° Noëlville Lower Go Home Domain (units 15 to 18) 65 3 10 o ic AWENDA 36 19 Weakly foliated to gneissic, mafic intrusive complex 15 45 Para-amphibolite tectonostratigraphic boundaries) (indicated by triangles) 85 33 17a Anorthosite, gabbroic anorthosite, minor gabbro country rock units (commonly found along 20 Lake 66 47b 47a 50 24 47a Deer 63 36 7 18b Small outcrops of unit 48a or 48b hosted by adjacent Island 85 18b 25 26 85 47 48c 19 42 55 26 45 33 47a 13 10 26 20 consisting of gabbro, anorthosite and ultramafic rocks 64 80 Hornblende diorite, gabbro 47c 50 26 Weakly foliated to gneissic metagabbro, primary 48b Bay 80 20 Beach 30 20 10 30 Wolverine 14 14 34 46 Home 69 75 17a 24 21d 19c 68 25 56 45 32 8 Calc-silicate gneiss Mafic Intrusive Rocks, Anorthosite Suite 47 80 5 21 Pink to grey marble 21c Ojibway Gneiss Association (units 19 and 20) Go 67 66 17b 51 61 18b 43 85 65 Unit 50a, with associated pink granite and grey 21b country rock units (indicated by dots) 22 18b 18b horizons igneous texture commonly preserved Little 60 60 4 15b 31 paragneiss and schist ("Dillon schist") with quartzite Intermediate Intrusive Rocks 69 43 BAXTER TP Park 30 11 Alban Waubamik Dillon Mafic Intrusive Rocks 48 50 42 10 Bayview 30 MATCHEDASH TP 38 18 Medium to dark grey, biotite-rich quartz-plagioclase Unsubdivided pink and grey leucocratic gneiss 14 3 12 5 55 15b Beau sole Sawlog Bay 68 60 19 15a 70 18b Metasedimentary Rocks Weakly foliated to gneissic, grey hornblende-biotite granodiorite and monzodiorite 41 15b 21 Weakly foliated to gneissic, grey tonalite with associated 62 18b 49 35 8 84 50b 20 70 26 Agreement (ERDA) signed by the governments of Canada and Ontario. Universal Transverse Mercator (UTM) co-ordinates are in North Unit 51a, with associated granite and monzonite minor tonalite 65 20 Harbour 15b Bay 18 Dark grey dioritic orthogneiss, possible hypabyssal intrusion (circa 1450 Ma) granodiorite, locally potassium feldspar megacrystic, 64 South 36 30 22b Grey tonalitic orthogneiss 57 65 40 Intermediate Rocks Weakly foliated to gneissic, pink monzonite, minor granodiorite 64 36 15 50a 31 47a 15 47 2 22 Intermediate to Felsic Intrusive Rocks Chute 54 60 10 18b Honey 50 Tonch 65 72 18b 12 24 45 30 Island 80 50 71 8 South Bay Harbour PARK 51 60 16 Unit 52a, strongly foliated to protomylonitic PROVINCIAL 28 33 15b 30 75 Honey Royal 69 71 Island 65 52 20 78 Unit 52a, with associated granite and quartz monzonite, 21a Big 23 73 51b 44 18b 35 75 25 70 5 grey, migmatitic leucogneiss syenite SIX MILE LAKE 25 25 10 Island 45 37 45 40 Felsic Rocks Pink, migmatitic, sugary leucocratic gneiss and subordinate Felsic to Intermediate Intrusive Rocks 51a gf 28 15b 20 Mermaid 40 20 56 45 7 51 30 7 18b 56 Beausoleil 43 18b 9 Little Bay Bay 25 65 42 23 22a 30 35 60 Bay 16 Beausoleil Turtle 20 Pink, leucocratic granite, locally potassium feldspar 72 18b 15 15b 30 20 20 4 Grey, layered quartzofeldspathic gneiss containing commonly potassium feldspar megacrystic 15 35 35 10 21 46 14 16 North 20 74 4970000m 52b 30 9 Deer Island 40 18b 23 24 Intermediate to Felsic Rocks Felsic Intrusive Rocks 65 30 45 45 52 52c 50 51a 29a 45 Georgian Bay 73 5 25 15b 45 55 85 28 30 71 20 Lake 37 48 33 13 Fairy 10 29a 55 6 34 Island Sand Bay Gneiss Association (units 21 to 24) 20 60 only parallel tectonic ALLOCHTHON-PARAUTOCHTHON BOUNDARY megacrystic Landing 30 subsidiary agreement to the Economic and Regional Development P.3548 Britt interpreted; trend layering and/or TECTONIC CONTACT WITH SUBJACENT LOWER GO HOME DOMAIN: Shawanaga Domain (units 19 to 24) Ontario 1985 Mineral Development Agreement (COMDA), a Red Bay 15b 14 the five-year Canada Harbour Lineament, Compositional 35 Intermediate to Felsic Rocks hornblende, biotite, epidote Wood 35 24 29b 20 74 30 85 23 Fraser Bank 35 51a 60 69 20 20 INTRUSIVE CONTACT 52a 80 55 30 30 15b 53 30 28 Smooth 6 33 7 ha 80 50 40 C SYMBOLS Grey, migmatitic tonalitic and granodioritic orthogneiss COMMONLY CONTAINING GARNET 66 Bay Geological Synthesis, funded as part of Trout Creek Felsic Rocks "SINGLE CYCLE PLUTONIC ROCKS", VARIABLY 70 48b 28 st o Buck 50b Island nashene 20 Bearshead Lake mapping program, Project C.2.3, Georgian French River Pink, sugary leucocratic granite gneiss Lake 6 Thibodeau L DEFORMED AND MIGMATITIC ORTHOGNEISS, 51a 26 coarse-grained, locally ophitic textured, metagabbro el nn 10 50 Mapping was conducted as part of a three-year 69 Mafic Rocks Pere Brebeuf Gneiss Association (units 25 and 26) Mafic Intrusive Rocks, Coronitic Metagabbro Suite Dark green to black, weakly foliated to gneissic, medium- to 70 40 Grey, migmatitic tonalitic and granodioritic orthogneiss Layered to podiform calc-silicate gneiss 70 12 Island 18b 55 18b 15b 80 30 Starr's 55´ 18b 50 50 20 65 Island 12 27 PROVINCIAL 10 Thompson's 29a Governor 20 AWENDA 73 48b correspond to a suite or a complex. Geological Survey. Killarney Unit 54a, with associated anorthosite and gabbro pods (circa 1165 Ma) 45 30 30 53 60 70 60 29a Metasedimentary Rocks 27 25 50 45 70 72 Giants 55 65 40 30 51a Island If it were decided to Mafic orthogneiss, amphibolite Weakly foliated to gneissic mafic rocks of unknown 75 Cedar Nook 30 28 and slivers 10 50 50b 54b Crooked 25 72 metamorphism or intrusion of mafic dikes. 1983 North American Stratigraphic Code, in most cases, they would 29b Mafic Rocks facies metamorphism and variably retrogressed Bay Bay 20 48b 35 65 35 Webber Culshaw et al. (1988), that is primarily based on rock type, but which formally name a "gneiss association" as a lithodemic unit under the protolith and of varied age, subjected to eclogite 73 12 gneiss association is an informal stratigraphic term, introduced by This map is published with the permission of the Director, Ontario Byng 54 11 15 WITHIN THE GRENVILLE PROVINCE 76 24 Thus, not all map units in the legend may appear on the map face. Intermediate to Felsic Rocks Grey, heterogeneous, leucosome-rich (>25%), 2 km NTS References: 31 D/13 46° 75 60 80 MESOPROTEROZOIC 54a 44 16 Maps P.3548, P.3549, P.3550, P.3551 and P.3552. also may contain information with respect to plutonic history, 29 1 © 81° 54 33 30 10 54 This is a legend common to Ontario Geological Survey Preliminary 77 PARK 50 Lake 28 26 Ship 40 34 3 24 This legend is a field legend that locally incorporates the results of A 0 Queen's Printer for Ontario, 2004. laboratory investigations, including petrography and geochemistry. c INTRUSIVE CONTACT 57 35 Straight and mylonitic gneiss derived from units 1a and/or 1b a No Unit 1a, with minor amounts of unsubdivided polycyclic migmatitic granodioritic gneiss PROVINCIAL 37 30 66 12 34 35 Big 23 80 40 16 70 25 Island Burnt 20 33 15 20 Wabeck 1c LOCATED WITHIN THE PARRY SOUND SHEAR ZONE Brown weathering, fine- to medium-grained diabase McCrae 60 61 60 1b b HIGH-GRADE METAMORPHISM 40 51a 70 (590 Ma) Lone Lake 48b 80 29 25 Island Metasedimentary Rocks Mafic Intrusive Rocks (Grenville diabase dike swarm) GIBSON RIVER 50 50b 14 19 40 Aberdeen 47 30 16 Island 70 leucosome older than the dikes is observed Crooked 18b 51a 30 35 70 28 15b 60 15b 75 25 15a 22 Arthur 15c Eshpabekong 76 33 25 35 45 50b 35 40 75 Island 25 20 50 20 21 25 30 r ek 5 29a 45 51a 35 metamorphosed mafic dikes (amphibolite). Pine Island Gneiss Association (units 27 to 29) 69 re C 10 Portage Bone 12 78 18b ry 12 48b 40 30 1000 m Mostly medium-grained, moderately foliated to gneissic, pelitic and garnet-rich gneiss interlayered with NEOPROTEROZOIC 55 6 50a 20 84 Gibson Riv e 1 15 Franceville 47 Island 38 15b 35 1a migmatitic, granodiorite to tonalite containing Upper Go Home Domain (units 25 to 29) ng Hu Stocking's 45 1 PENETANGUISHENE AREA Scale 1:50 000 Para-amphibolite and unsubdivided paragneiss; includes Gneiss Association (unit 30) Gibson Lake 70 32 5 Intermediate Migmatitic Rocks Mafic and Metasedimentary Rocks grey to white sublithographic to lithographic limestone) PRECAMBRIAN GIBSON TP 50 25 8 35 Mafic Rocks UNCONFORMITY 26 45 70 37 45 77 33 Cognashene 40 Quartzite, minor associated paragneiss Grey biotite-muscovite-garnet-kyanite gneiss and schist 26 65 70 Lake 18b 85 85 87 5 49 sillimanite gneiss; minor quartzite, calc-silicate gneiss TECTONIC CONTACT (SUSPECT) WITH THE SHAWANAGA DOMAIN, 70 22 locally with garnet-hornblende and garnet-kyanite and granodiorite orthogneiss Gneissic Rocks Structurally Below the Lighthouse 50 45 Layered, pink to grey quartz-feldspar-biotite paragneiss, Layered, migmatitic, grey tonalite, minor trondhjemite, grey to blue-grey interbedded limestone and dolostone, arkosic sandstone, pebbly sandstone, siltstone and shale) 26 Ontario Geological Survey PRECAMBRIAN GEOLOGY and metasedimentary gneiss 79 50a 50b 38 Intermediate to Felsic Rocks with Metadiabase Dikes quartzofeldspathic gneiss and minor quartzite Chemical Sedimentary Rocks Lake 51a 20 Mafic monzodiorite gneiss and Shadow Lake Formation (calcareous red and green Lalonde 46 78 66 St gn 80 Mafic gneiss; minor metagabbro, anorthositic gneiss 3b Unsubdivided: includes Gull River Formation (light brown- 48b 55 15 25 56 Lake 60 75 4980000m 15b 77 48b 48b 51a Bear 75 45 35 65 10 30 85 31 MIDDLE ORDOVICIAN Lake 35 3a Metasedimentary Rocks 2 ORDOVICIAN 80 80 32 29b ve 50 40 32 60 Ri 48b 50b 29a 79 sh 20 80 30 Mafic Rocks 3 Amphibolite Boot M 50a 60 10 84 80 iv er s on R Gib 51a us q 87 25 Mafic and Metasedimentary Rocks Bustard Islands Gneiss Association (unit 1) PALEOZOIC 81 sh 50a 60 Predominantly grey gneiss with pink granitic leucosome 33b 51a 50 75 4c UNCONFORMITY 33 47 quartzite 33a 51a 47 Pink, sugary leucocratic gneiss Glacial deposits; sand and gravel, clay 32 67 Unsubdivided pink and grey leucocratic gneiss 4b Lighthouse Gneiss Association (units 31 to 33) 20 65 30 18b 29a 34 82 60 81 4a Para-amphibolite, layered mafic gneiss, paragneiss and PLEISTOCENE 70 83 Intermediate to Felsic Rocks 4 Mafic Rocks : MAP P.3552 Lake, stream and swamp deposits Lake Lake Potters 20 63 51a 35 RECENT Lake 48b 28 Armer Bay Gneiss Association (units 34 and 35) Quartzite, minor associated paragneiss and para-amphibolite 25 60 Multicomponent layered gneiss and migmatite, minor amphibolite Lafarce Gibson 50 62 Intermediate to Mafic Migmatitic Rocks 5 Parry Sound Domain (basal) (units 30 to 35) Sahanatien 60 10 Key Harbour Gneiss Association (units 2 to 5) LOCATED WITHIN PARRY SOUND SHEAR ZONE CENOZOIC zU 1047 ± 2 13 51a PHANEROZOIC Webster Lake 48b 4 50 22 10 46 Home 10 45°00´00 51a 15 20 THRUST CONTACT WITH PARRY SOUND DOMAIN (BASAL), 05 604000m WOOD TP 25 35 03 02 01 600000m 99 98 97 Lake 15 Lake 8 42 Go Go 62 15 51a Lake 24 51a 25 Swan Lake Home 50a 64 Coldwater Go 35 45°00´00 96 95 94 93 92 91 590000m 89 88 87 86 85 abc liability. Users should verify critical information. Issued 2004. Information from this publication may be quoted if credit is given. It is recommended that reference to this map be made in the following form: Culshaw, N.G., Corrigan, D., Ketchum, J.W.F., Wallace, P. and Wodicka, N. 2004. Precambrian geology, Penetanguishene area; Ontario Geological Survey, Preliminary Map P.3552, scale 1:50 000. 55´ 560000m 59 58 57 64 63 62 61 45°15´00 31 23 25 31 PARRY ISLAND I.R. 16 Parry Island 47a 47a Baker Group 5010000m 50 65 60 75 72 34 57 55 40 14 20 86 47a 75 40 37 Group 37 50 Conlin Island Island 58 48 no bu au W 37 48 37 70 70 40 zU 1151 ± 1 66 an 57 61 ne l 37 80 37 72 70 55 61 Matthews 37 Ajax 41 53 69 Vanderdasson Island Island 70 44 64 39 70 87 48 30 63 76 66 85 60 37 71 30 73 38 37 70 75 37 72 72 99 72 40 65 37 65 57 58 39 85 37 55 Georgian Bay 36 29 40 96 Loon 50 31 35 38 40 32 95 20 5 8 28 75 51 45 40 39 26 21 44b 35 14 8 27 23 zU <1121 ± 4 29a 25 30 26 22 30 40 O'DONNELL POINT 21 10 30 POINT 23 44b 47 32 13 29b 30 10 32 40 24 18 23 44 29a 10 27 40 36 27 14 18b 20 65 26 35 35 30 32 51 25 14 18b 18b 60 51a 82 27 50b 88 36 Western Islands 5 10 11 45 40 9 50 45 34 Island 30 38 70 51a 30 50 25 38 16 29a 10 20 15a 15a 16 Galbraith Starr Island Island 13 55 80 41 29 45 30 45°00´00 550000m 80°22´34 51 52 20´ 53 54 55 56 57 58 59 15´ 560000m 61 62 63 64 65 10´ 66 67 68 69 570000m 71 72 05´ 73 74 75 76 77 78 80°00´00 37 580000m 81 83 84 40 36 60 Marble; may be associated with rusty graphitic schist 15c Calc-silicate gneiss 4984000m 69 Coldwater Lake 87 88 89 590000m 91 92 50´ 93 trend only, limbs dip Fold axis; minor fold, 94 Ardbeg Dunchurch Pointe au Baril Station 69 Waubamik Dillon Synform, interpreted; (with plunge) unknown generation, Fold axis; minor fold, in opposite directions (with plunge) Mineral occurrences, Fold axis; minor fold, discretionary m-asymmetry occurrences (as (with plunge) classed by the Mineral Deposit Inventory (MDI)) (interpreted) 11 Orrville 35 Dorset Rosseau Port Sydney 141 BAY Tobermory Dwight 60 Huntsville Parry Sound 117 Sans Souci Baysville MacTier 118 P.3551 Bala 400 Lion's 118 Bracebridge 169 45° Head 45° Edenhurst Honey Harbour Purple Valley LAKE Penetanguishene Gravenhurst P.3552 Norland Washago 12 Wiarton HURON 81° Shallow Nottawasaga Bay Leith 26 Woodford Midland 11 80° 12 169 79° Orillia 48 Thornbury 427m Location Map Fenelon Brechin 1 cm equals 25 km SOURCES OF INFORMATION Thematic information on this map is tied to a digital base map derived from maps 41 H/1 and 31 E/4 of the National Topographic System, scale 1:50 000. Universal Transverse Mercator (UTM) co-ordinates are in North American Datum 1983 (NAD83), Zone 17. Location of isotopic Limit of mapping; Novar Broadbent Nobel P.3550 Kearney Sprucedale McKellar Red Bay s-asymmetry Magnetawan Burk's Falls P.3549 bA 978 ± 6 age determination denotes limits of area mapped during this survey Geological Survey of Canada Ontario Department of Mines 1953. Aeromagnetics, Lake Joseph; Geological Survey of Canada Ontario Department of Mines, Geophysical Map 126G, scale 1:63 360. Geological Survey of Canada Ontario Department of Mines 1965. Boundary of local to Aeromagnetics, Sans Souci; Geological Survey of Canada Ontario Department of Mines, Geophysical Map 1495G, scale 1:63 360. retrogression of mineral assemblages to amphibolite-facies ornamentation is on the lower grade (amphibolite-facies) side (south) Ontario Geological Survey 2002. (MDI2) Mineral Deposit Inventory Version 2 October 2002 Release; Ontario Geological Survey, Digital Data. Cosca, M.A. 1989. Cooling and inferred uplift/erosion history of the Grenville orogen, Ontario: constraints from Argon-40/Argon-39; unpublished PhD thesis, University of Michigan, Ann Arbor, Michigan, 223p. Culshaw, N.G., Corrigan, D., Drage, J. and Wallace, P. 1988. Georgian Bay geological synthesis: Key Harbour to Dillon, Grenville Province of Paper 88-1C, p.129-133. ABBREVIATIONS Cumming, G.L., Wilson, J.T., Farquhar, R.M. and Russell, R.D. 1955. Some dates and subdivisions of the Canadian Shield; Geological Association of Canada, Proceedings, v.7, p.27-79. Ag ...............................................................silver Au .................................................................gold Lowdon, J.A. 1960. Age determinations by the Geological Survey of Ce .............................................................cerium Canada, Report 1: isotopic ages; Geological Survey of Canada, Paper Cu.............................................................copper 60-17, 51p. Fe ..................................................................iron fel ............................................................feldspar Stockwell, C.H. 1982. Proposals for time classification and correlation gt ...............................................................garnet of Precambrian rocks and events in Canada and adjacent areas of the mica ............................................................mica Canadian Shield. Part 1: A time classification of Precambrian rocks and Mo...................................................molybdenum events; Geological Survey of Canada, Paper 80-19, 135p. Ni................................................................nickel van Berkel, J.T. and Schwertdner, W.M. 1986. Precambrian geology of peat ..............................................................peat the Moon River area, Muskoka and Parry Sound districts; Ontario REE......................................rare earth elements Geological Survey, Preliminary Map P.2954, scale 1:50 000. 40 SM ..................................sulphide mineralization Wasserburg, G.J. and Hayden, R.J. 1955. Ar St an .......................................stone, anorthosite Cosmochimica Acta, v.7, p.51-60. Grey biotite leucogneiss of granodioritic composition -K 40 dating; Geochimica et Th ............................................................thorium Wodicka, N., Parrish, R.R. and Jamieson, R.A. 1996. The Parry Sound U ............................................................uranium domain: a far-traveled allochthon? New evidence from U-Pb zircon Zn..................................................................zinc geochronology; Canadian Journal of Earth Sciences, v.33, p.1087-1104. Magnetic declination approximately 10°42'W in 2004. mA = muscovite Ar/Ar date, in Ma Geology not tied to surveyed lines. kK = potassium feldspar K/Ar date, in Ma Metric conversion factor: 1 foot = 0.3048 m. uW = uraninite Pb/Pb date, in Ma zU = zircon U/Pb date, in Ma CREDITS Migmatitic Rocks of granodioritic to monzodioritic composition Geology by N.G. Culshaw, D. Corrigan, J.W.F. Ketchum, P. Wallace and N. Wodicka, 1987 to 1990. Migmatitic Rocks Grey, leucocratic, migmatitic hornblende-biotite-garnet Mafic Rocks orthogneiss of tonalitic to granodioritic composition 12 Geological compilation by N.G. Culshaw, 1991 and 2004. Metasedimentary Rocks Unclassified paragneiss 11 Metasedimentary Rocks 45°00´00 95 Geology, legend and mineral deposit information reviewed by R.M. Easton. Cartographic production by S. MacLean. Felsic Rocks 10 Metasedimentary Rocks Intermediate to Felsic Granulites To enable the rapid dissemination of information, this map has not received a technical edit. Discrepancies may occur for which the Ontario Ministry of Northern Development and Mines does not assume 9 Metasedimentary Rocks liability. Users should verify critical information. Grey, migmatitic, leucocratic garnet-biotite paragneiss, locally with sillimanite; pink leucosome, may contain garnet, Intermediate to Felsic Granulites (layered) Issued 2004. Information from this publication may be quoted if credit is given. Bayfield Gneiss Association (units 6 to 8) Intermediate to Felsic Rocks Pink, sugary leucocratic gneiss Intermediate to Felsic Granulites (retrogressed) 7 Intermediate to Felsic Intrusive Rocks 7a Unsubdivided grey and pink, variably layered, highly strained orthogneiss, in places with recrystallized 7b Mafic Rocks Grey, leucocratic, migmatitic hornblende-biotite-garnet orthogneiss of tonalitic to granodioritic composition Metasedimentary Rocks 36a Layered paragneiss, garnet-rich granulite 36b Marble, calc-silicate tectonic breccia Metasedimentary Rocks 6a Grey, leuco- to mesocratic garnet-biotite paragneiss, commonly with sillimanite; locally graphitic and rusty weathering Calc-silicate and amphibolite gneiss associated with garnet-biotite paragneiss of unit 6a 20 86 15b 6b 400 70 55´ Unclassified paragneiss granulite or gneissic metagabbro 85 70 42 85 15a Unsubdivided, layered, predominantly mafic two-pyroxene 42 82 Pink, sugary, layered leucocratic gneiss 43b (granodiorite, tonalite to diorite) orthogneiss containing 40 50 20 46 55 38 51a 51a Ahmic Harbour Grey, migmatitic, leucocratic hornblende-biotite orthogneiss 6 15 Metasedimentary Rocks potassium feldspar megacrysts 70 18b 79 40 50 Mafic Rocks (e.g., unit 39 or 40); pegmatite veins may be common Lake Byng wR = whole rock Rb/Sr date, in Ma 8 18a 25 60 4 48b 80 29a 15 20 20 Monzonitic to granitic orthogneiss granulite 30 37 40 68 Big Island 80 30 64 25 4984000m 42 43a 50 40 50a 53 r 15 15 49 29a 40 unknown generation, South River Sundridge Magnetawan Dyer's Bay mK = muscovite K/Ar date, in Ma Unsubdivided, buff to grey weathering, layered, feldspathic 15 55 80 65 34 18b Lake 17b Britt Domain (units 1 to 14) evidence of retrogression from a granulite facies precursor Home 50 30 80 15 55 51a 39 86 49 26 15 28 Pine Islands Tate 27 60 6 45 30 80 85 80 40 50 Port Loring North P.3548 Britt 6 z-asymmetry 35 Pakesley Harbour muscovite, magnetite 87 Island 15 85 only bK = biotite K/Ar date, in Ma Intermediate to Felsic Rocks Unsubdivided, grey to buff weathering, orthopyroxene- Rabbit 38 Unclassified granitoid orthogneiss Unsubdivided, grey, foliated to gneissic, intermediate 47b 40 83 40 Go 30 17a Rusty weathering, graphitic paragneiss Lake 45 Intermediate to Felsic Rocks Quartzite Buff to pink weathering, leucocratic granulite 88 35 e iv 75 30 GIBSON TP Lake 64 Pink to grey, migmatitic leucogranite to granodiorite Pink, layered, leucocratic paragneiss 41 R 51a 60 65 Interlayered amphibolite, semi-pelitic gneiss and Pink to grey leucocratic gneiss 18b PARAUTOCHTHON NORTH OF PARRY SOUND DOMAIN orthogneiss Lunnen 50b 44 44c 18a BASE OF LOWER GO HOME DOMAIN NOT OBSERVED bearing intermediate (granodiorite, tonalite to diorite) Island Surerus 30 75 40 5 Turtle 48b 80 Island 10 Key Commanda St gr ...............................................stone, granite 15 PARRY SOUND DOMAIN (INTERIOR) sh 32 40 60 50 67 15a 18b 86 Lake 20 62 45 65 Gunn Amphibolite er ua 65 50b Mafic orthogneiss 44b TECTONIC CONTACT WITH SUBJACENT 60 31 28 80 67 Flatrock Lake 51a 45 15a iv 35 61 50 Leclairc Lake 20 51a 87 44a Felsic Rocks Mafic orthogneiss GIBSON I.R. 31 35 Gray 55 60 60 35 46° Restoule Si .................................................................silica Mafic and Metasedimentary Rocks 89 R 70 45 25 30 30 60 35 55 42 48 24 50a 32 Grey hornblende-epidote-biotite tonalitic orthogneiss Fossmill Nb ...........................................................niobium Intermediate to Felsic Rocks Parry Sound Domain (interior) (units 36 to 41) 38 60 10 oo n 15b 51a 20 19c 30 50 50 Island 21 M 84 87 35 Kiosk 79° Powassan Digital drafting by S. Josey. 48 53 20 47 10 52 Lake 27 Grey, migmatitic, tonalitic to granodioritic gneiss with Honey Harbour Gneiss Association (units 15 to 18) Amphibolite 30 80 56 55 38 64 42 Mu sq Bands 18b 19b PARAUTOCHTHON SOUTH OF PARRY SOUND DOMAIN 13 Irvine 70 43 69 20 45 18 Grey metatextite with pink, hornblende-epidote-bearing 47 58 51a Tadenac 75 10 65 45 4990000m 18b Lake 30 8 55 South Group 74 51a Migmatitic Rocks ALLOCHTHON-PARAUTOCHTHON BOUNDARY 14 400 49 55 26 Intermediate to Felsic Rocks 80° Noëlville Pickerel Blackstone Lake Gneiss Association (units 42 and 43) 73 58 Steers 91 80 55 50 55 57 20 20 Quartzite Nadeau Island Gneiss Association (units 9 to 14) 25 9 16 Grey, migmatitic layered gneiss quartzite 25 15 63 13 32 47a 65 38 36 45 Adams 75 20 12 35 30 11 45 Bay 50 Pink, sugary, layered leucocratic gneiss 46b 44d 75 47 15 23 Tadenac Island 18 46a 47a 32 80 Para-amphibolite 21e 11 Alban (NADEAU ISLAND GNEISS ASSOCIATION): 55 80 50 10 10 29a 80 48b Galla Lake 85 10 50 66 70 30 10 2 34 Peacock 18 20 45 32 51a 42 15a 45 22 51a 89 32 44 Bay 20 47a 67 30 40 60 Big David Lake 27 46b 42 80 (trend only, inclined, TECTONIC CONTACT WITH SUBJACENT BRITT DOMAIN Felsic to Intermediate, Layered or Migmatitic Rocks Lake 45 5 45 60 25 60 4990000m Galla Creek 44 45 60 18 29a ers Lake Lake 18b Lower 56 60 in M 25 27 70 52 40 35 35 34 80 2 interpreted; trend varied amounts of pink leucosome White McMaster 50 28 21d leucosome Grey, migmatitic tonalite to granodiorite orthogneiss 38 35 58 60 45 45 58 47 60 Calc-silicate gneiss 19a 6 44c 40 48b 60 46 92 15 62 44 25 10 35 75 80 U 19 16 68 56 42 65 30 20 89 16 55 30 18b 60 22 19 55 21c Unsubdivided pink and grey leucocratic gneiss Moon River Gneiss Association (units 44 to 46) 47 32 47 05´ 60 38 25 11 6 29b 65 47a 55 10 20 24 45 20 Moon River Subdomain (units 42 to 46) 60 46a 50 14 65 57 30 I.R. 79 Ri ve r 52 56 65 38 53 72 46b 45 70 30 25 47a 12 17 on Foliation granulite-facies 17 45 61 37 34 MOOSE POINT 45 25 32 9 30 33 10 37 47a M o 35 Pink to grey marble Ojibway Gneiss Association (units 19 and 20) ALLOCHTHON 8 32 25 30 18b 30 21b Ontario 1985 Mineral Development Agreement (COMDA), a GEORGIAN extensive INTRUSIVE CONTACT 68 42 32 34 25 29a 20 12 50 30 32 5 horizons 18 60 52 40 hanging-wall side Medium to dark grey, biotite-rich quartz-plagioclase paragneiss and schist ("Dillon schist") with quartzite 50 35 Metasedimentary Rocks 21a EARLY MESOPROTEROZOIC to 45 60 21 LATE PALEOPROTEROZOIC 40 45 42 35 Moose Bay 34 30 2 25 27 30 35 91 e Bay T w elv e Mil 2 80 14 47 15 27 25 20 35 St an 44b 29a 45 92 10 35 26 I.R. 79 O'Donnell Channel 5 Small outcrops of unit 47a or 47b hosted by adjacent 94 58 25 30 25 45 57 47a 28 MOOSE PROVINCIAL NATURE RESERVE 44c 21 31 23 05´ 85 52 47 53 Dark grey dioritic orthogneiss, possible hypabyssal Lower Go Home Domain (units 15 to 18) 80 42 Grey tonalitic orthogneiss tectonostratigraphic boundaries) (indicated by triangles) 56 42 (trend only, inclined, Geological contact Weakly foliated to gneissic, mafic intrusive complex 60 56 38 51 Anorthosite, gabbroic anorthosite, minor gabbro country rock units (commonly found along 95 Myers 75 50 34 82 68 47a 47c 56 44c 25 20 9 37 46b FREEMAN TP 80 16 38 50 55 67 70 6 24 60 8 44c 27 80 55 40 20 Weakly foliated to gneissic metagabbro, primary Small outcrops of unit 48a or 48b hosted by adjacent Lake Lake 50 46b the five-year Canada Ontario; in Current Research, Part C, Geological Survey of Canada, 70 80 55 trend only, teeth on intrusion (circa 1450 Ma) Unit 50a, with associated pink granite and grey Buckhorn St an 47a 70 Intermediate Rocks 22b consisting of gabbro, anorthosite and ultramafic rocks 21 Felsic Rocks 22a Weakly foliated to gneissic, grey hornblende-biotite 48c 47b 25 St gr 75 40 Unit 51a, with associated granite and monzonite Hornblende diorite, gabbro 47a Gooley 44b Intermediate to Felsic Rocks Weakly foliated to gneissic, pink monzonite, minor Mafic Intrusive Rocks, Anorthosite Suite 47 Haggart Lake 9 65 21 15 38 38 37 47a 10 26 26 30 Unit 52a, strongly foliated to protomylonitic 96 36 Lake 65 unknown generation prospects, 22 country rock units (indicated by dots) 40 44c 35 44c 35 22 93 58 Thrust fault, interpreted; subhorizontal) grey, migmatitic leucogneiss Unit 52a, with associated granite and quartz monzonite, 48b 36 54 4 48 23 44b 47a 45 21 20 44c 29 North Group 30 38 71 22 Island Western Islands 47 38 65 47a 15 21 45 45 46a foliation; Antiform, interpreted; Pink, migmatitic, sugary leucocratic gneiss and subordinate igneous texture commonly preserved 45 45 75 40 47a North River 27 40 52 94 57 48a 4 44a 25 24 23 Mafic Intrusive Rocks 48 2 Vaughan Bay Geological Synthesis, funded as part of Inlet mineral assemblages; 97 57 26 Moon 42 40 Lake 51 Arnolds Bay 25 40 37 46b 47 31 25 75 26 47a 8 25 47 45 26 70 60 65 47 52 18 14 85 15 42 trend only Lineation (with plunge, hornblende, biotite, epidote Intermediate Intrusive Rocks 15 28 46b Pink, leucocratic granite, locally potassium feldspar granodiorite and monzodiorite 50 70 35 65 10 18 PARK 68 18 35 Grey, layered quartzofeldspathic gneiss containing Weakly foliated to gneissic, grey tonalite with associated 80 34 36 25 49 75 52 52 35 15 55 24 granodiorite 46b 80 20 44a 50b 98 27 48 30 layering and/or in opposite directions minor tonalite Foot's Bay 27 65 46a 65 65 Fault, interpreted; vertical) 35 granodiorite, locally potassium feldspar megacrystic, 24 53 25 45 31 Intermediate to Felsic Rocks Intermediate to Felsic Intrusive Rocks 50a 20 20 11 44c 30 20 30 60 47 25 50 47 63 33 38 38 20 77 42 80 41 40 48 40 13 40 44c 22 28 36 PROVINCIAL 38 64 70 24 34 MASSASAUGA 30 41 50 33 37 31 73 75 42 70 9 15 20 25 U 66 35 60 32 Lake 51b 612 86 Park Lake 65 70 50 Eagle 34 99 80 37 Compositional vertical) Felsic to Intermediate Intrusive Rocks 51a 23 50 30 51 27 45 51 Stewart U 53 46a 26 52c 37 71 65 44 44a 24 River 37 43b 20 36 10 39 35 40 28 38 Dock 35 46 45 47 55 U mapping program, Project C.2.3, Georgian Trout Creek parallel tectonic Felsic Rocks ALLOCHTHON-PARAUTOCHTHON BOUNDARY 25 55 35 TECTONIC CONTACT WITH SUBJACENT LOWER GO HOME DOMAIN: syenite 30 42 42 30 80 25 55 18 10 Bay 15 Moon Bay 33 43 Manitou 60 45 80 35 44c 45 30 25 44b 65 Mapping was conducted as part of a three-year 46° Lineament, commonly potassium feldspar megacrystic Lake MacTier 37 45 Moon 67 26 42 44b 46b 38 66 23 48 24 25 44 40 55 43 55 55 60 68 27 Island 30 46 35 43b 67 27 47b 24 70 2 Lake 40 52b 5000000m 69 36 75 43a 35 26 50 40 THE 30 18 25 77 43 75 37 68 21 49 45 37 66 30 75 32 25 megacrystic 40 30 67 28 44 30 55 peat 30 SYMBOLS Pink, sugary leucocratic granite gneiss Felsic Intrusive Rocks 52a Ricketts Lake 36 MacRae gt 30 Island 50 e 31 55 30 35 22 46a 75 70 52 10 60 63 25 Ju n iper La k 26 COMMONLY CONTAINING GARNET Lake 47 peat 77 44a 54 43b 66 50 01 U 39 30 44c 62 Moon 36 55 75 31 60 40 47a 27 45 30 31 39 63 82 75 62 47 37 62 65 80 40 25 44 37 32 35 80 30 26 54 zU 1317 ± 24 50 70 43 29 46 70 41 65 75 Lake 44 DEFORMED AND MIGMATITIC ORTHOGNEISS, 55 18 55 35 41 64 48 70 56 46 80 52 34 33 38 Woods 50 35 Little Juniper "SINGLE CYCLE PLUTONIC ROCKS", VARIABLY 59 30 Fenton Geological Survey. French River Metasedimentary Rocks trend only, limbs dip 60 38 46b 15 15 58 36 44 42 Bay 20 44 42 26 32 35 46 57 This map is published with the permission of the Director, Ontario 69 Sand Bay Gneiss Association (units 21 to 24) 43a 65 Queen's Printer for Ontario, 2004. 81° Shawanaga Domain (units 19 to 24) 52 56 45 44b 13 50 60 61 29 41 Kapikog Lake 60 45 © Panache coarse-grained, locally ophitic textured, metagabbro 35 40 15 18 36 Mafic Rocks Layered to podiform calc-silicate gneiss 56 80 47 27 2 km Agreement (ERDA) signed by the governments of Canada and Ontario. Mafic orthogneiss, amphibolite 25 46a 42 28 1 subsidiary agreement to the Economic and Regional Development Grey, migmatitic tonalitic and granodioritic orthogneiss INTRUSIVE CONTACT 53 35 44a 68 50 31 46b 50 32 Bay 65 52 31 60 correspond to a suite or a complex. 29b Dark green to black, weakly foliated to gneissic, medium- to 23 C re ek 46b 65 43 30 40 42 48 75 44 65 50 50 62 55 65 23 37 65 70 36 56 97 47 70 62 60 50 60 43 18 r 1983 North American Stratigraphic Code, in most cases, they would Mafic Intrusive Rocks, Coronitic Metagabbro Suite (circa 1165 Ma) 02 41 45 31 53 10´ 51 46 50 C o n g e 35 If it were decided to 29a Grey, migmatitic tonalitic and granodioritic orthogneiss 23 45 41 49 49 53 43b 50 Woods 40 47 75 29 45 70 70 40 43 40 40 48 er 70 38 21 45 75 30 44c 47a 55 41 20 iv 26 45 48 40 60 55 66 70 28 44 42 42 32 R 62 Sharpe Island 60 67 55 54 52 65 70 41 40 70 25 37 45 63 40 400 41 68 35 43b 82 57 40 35 80 metamorphism or intrusion of mafic dikes. Unit 54a, with associated anorthosite and gabbro pods and slivers 52 28 46 66 36 67 98 55 54 60 42 20 53 50 41 21 71 44c 38 55 30 70 Lake 40 Healey Lake 60 50 61 75 77 40 50 42 52 15 72 Moon Bay 60 85 50 84 66 31 70 40 71 North 45 45 40 54b 60 24 50 Hutcheson Culshaw et al. (1988), that is primarily based on rock type, but which Weakly foliated to gneissic mafic rocks of unknown facies metamorphism and variably retrogressed 03 55 60 46b 35 66 80 24 65 80 26 57 47a 63 gneiss association is an informal stratigraphic term, introduced by Intermediate to Felsic Rocks Pere Brebeuf Gneiss Association (units 25 and 26) protolith and of varied age, subjected to eclogite 27 32 Thus, not all map units in the legend may appear on the map face. formally name a "gneiss association" as a lithodemic unit under the Mafic Rocks 54a 27 43b 39 45 40 44a 42 Channel 69 46 42 72 32 63 50 La Force Lake 67 42 80 66 47 70 80 75 75 26 56 84 50 80 54 86 74 65 Wreck Island 80 30 42 27 Maps P.3548, P.3549, P.3550, P.3551 and P.3552. also may contain information with respect to plutonic history, Grey, heterogeneous, leucosome-rich (>25%), 0 Killarney 29 45 50 85 69 CONGER TP 19 62 35 64 24 35 37 40 56 56 35 36 40 85 40 38 37 71 66 55 36 65 5000000m e g 35 laboratory investigations, including petrography and geochemistry. This is a legend common to Ontario Geological Survey Preliminary A 1000 m NTS References: 41 H/1, 31 E/4 This legend is a field legend that locally incorporates the results of 30 43a 5 53 52 r 75 53 60 o n 57 25 30 65 73 HIGH-GRADE METAMORPHISM 54 54 63 38 67 23 39 80 26 25 45 iv e 70 50 20 65 40 Copperhead 65 18 25 40 Island 34 37 80 65 52 50 45 48 04 U,Th 50 38 MESOPROTEROZOIC WITHIN THE GRENVILLE PROVINCE 30 22 65 Lake Joseph 25 45 56 40 a 72 45 45 43a Straight and mylonitic gneiss derived from units 1a migmatitic granodioritic gneiss Lake Joseph 80 Unit 1a, with minor amounts of unsubdivided polycyclic and/or 1b c INTRUSIVE CONTACT Siding 80 68 32 65 35 45 80 74 52 Island 66 65 75 Barnard 36a 37 80 40 32 35 Moon 80 Harbour 30 Island 70 79 37 85 25 63 Wahsoune 66 35 60 R 44 56 37 62 75 45 80 80 25 47 C e 75 88 37 65 80 65 45 62 51 75 70 Blackstone 55 37 73 60 38 17 70 29 80 9 n 52 75 01 Island 75 39 42 o 82 10´ Miron 35 46 49 31 70 25 50 40 61 20 43b 1c LOCATED WITHIN THE PARRY SOUND SHEAR ZONE Brown weathering, fine- to medium-grained diabase Dock No leucosome older than the dikes is observed b 29 (590 Ma) 05 47 st Souci 63 55 70 28 85 73 44 59 70 52 54 40 ck 50 Sans 60 02 29 50 30 Metasedimentary Rocks Mafic Intrusive Rocks (Grenville diabase dike swarm) 55 Loucks Lake 64 45 CONGER TP Gneiss Association (unit 30) 75 20 23 70 la B 44 38 80 80 35 23 43 55 60 43 35 28 75 n oo M Island 14 50 56 40 30 73 43b 35 37 metamorphosed mafic dikes (amphibolite). Pine Island Gneiss Association (units 27 to 29) 45 35 70 70 Lake 40 peat 42 Para-amphibolite and unsubdivided paragneiss; includes 1b SANS SOUCI AREA Scale 1:50 000 Mostly medium-grained, moderately foliated to gneissic, migmatitic, granodiorite to tonalite containing Upper Go Home Domain (units 25 to 29) 37 61 72 35 56 44 67 72 58 50 18 60 50 55 74 Cu 30 37 60 42 Intermediate Migmatitic Rocks 1 Mafic and Metasedimentary Rocks NEOPROTEROZOIC 35 McQuillan 53 50 60 40 Amphibolite and metasedimentary gneiss PRECAMBRIAN 06 16 42 41 70 Little Blackstone Lake 41 75 43b Mafic Rocks TECTONIC CONTACT (SUSPECT) WITH THE SHAWANAGA DOMAIN, 40 55 42 44 sillimanite gneiss; minor quartzite, calc-silicate gneiss Quartzite, minor associated paragneiss Gneissic Rocks Structurally Below the Lighthouse 60 65 43b 50 37 45 43a locally with garnet-hornblende and garnet-kyanite and granodiorite orthogneiss grey to white sublithographic to lithographic limestone) 40 31 35 80 68 80 Layered, pink to grey quartz-feldspar-biotite paragneiss, Layered, migmatitic, grey tonalite, minor trondhjemite, Grey biotite-muscovite-garnet-kyanite gneiss and schist Bay Ontario Geological Survey PRECAMBRIAN GEOLOGY 33a UNCONFORMITY 65 15 30 Lake 50 45 47 10 70 50 73 70 77 Bay 70 Skidway 80 25 76 Rawson 26 85 Crooked 70 Fryingpan Port 60 Island 76 46 45 45 37 50 37 56 40 55 40 23 34 45 54 21 37 75 57 50 80 61 Island 71 45 65 Pennsylvania 39 65 70 80 40 Souci 40 76 68 64 66 64 31 80 85 60 45 70 37 52 72 63 84 42 Mafic monzodiorite gneiss Intermediate to Felsic Rocks with Metadiabase Dikes grey to blue-grey interbedded limestone and dolostone, Gordon 43b Mafic gneiss; minor metagabbro, anorthositic gneiss 3b Unsubdivided: includes Gull River Formation (light brown- arkosic sandstone, pebbly sandstone, siltstone and shale) 42 60 80 40 65 75 70 Island 03 75 37 Sans 58 PROVINCIAL PARK 36 3a Metasedimentary Rocks quartzofeldspathic gneiss and minor quartzite Chemical Sedimentary Rocks 36 45 70 67 Quartzite, minor associated paragneiss and para-amphibolite and Shadow Lake Formation (calcareous red and green 26 43a 15 43b 60 54 36 43 80 60 33 52 38 73 80 53 56 45 45 55 Echo 88 56 47 07 25 34 43a 45 Bay 36 Lake 22 40 45 THE MASSASAUGA 70 56 Island 52 70 72 25 35 60 60 52 72 52 82 Lake Lake 40 36 85 20 36 25 ek 39 39 04 56 50 Hines Bround 35 47b 35 20 44 60 45 40 75 35 85 37 Wilcox 70 16 60 37 65 37 40 Island 73 56 52 60 70 54 48 45 32 Gordon 20 30 42 26 85 Lake 74 88 Pauls 70 64 50 Lake 75 37 36a 81 69 56 Crane Lake 50 25 40 43a re C 39 39 39 49 37 70 25 Peanut Lake 67 68 37 69 80 60 10 41 58 46 15 56 36 Krapek Lake 45 Mafic Rocks 3 pelitic and garnet-rich gneiss interlayered with 25 34 Lake 73 31 MIDDLE ORDOVICIAN Stanley House 60 Lake 50 15 40 25 Lake Payne Oldfield Mafic and Metasedimentary Rocks t 36a 82 50 75 62 45 Warnica 58 58 64 Spider Lake Clear 35 40 37 37 60 80 80 5 05 51 60 55 zU 1300 ± 17 48 67 87 66 50 06 81 74 40 45 81 08 54 Lake Predominantly grey gneiss with pink granitic leucosome 1a a Islands 69 75 37 65 57 56 75 41 70 40 50 78 35 Island 40 65 20 45 40 4c ORDOVICIAN 44 37 45 45 43b 47b 56 37 47 65 22 17 39 55 Portage quartzite 33b 32 34 Nb,Si Pink, sugary leucocratic gneiss Bustard Islands Gneiss Association (unit 1) PALEOZOIC Lake 25 fel,U,Th, 48 60 37 85 61 35 51 33 UNCONFORMITY Tiffin 30 40 70 42 and till 09 40 50 70 70 50 73 78 43a Unsubdivided pink and grey leucocratic gneiss 4b 2 Glacial deposits; sand and gravel, clay Hamer Bay 75 R 37 64 40 14 29 55 45 Lake 26 57 38 70 36 Blackstone 50 82 70 41 25 6 Lake Nb 28 31 38 17 Burnt 30 Lake Lake 55 38 64 69 58 4a Para-amphibolite, layered mafic gneiss, paragneiss and Lighthouse Gneiss Association (units 31 to 33) 29 42 gt,mica 35 Stonehouse 11 56 40 85 Zr,Th,Nb, 75 65 70 37 65 74 48 26 Asperitas 40 55 35 69 43 60 40 80 Zn,Fe 82 Island 20 48a Cu,SM, Lake Lake 26 26 40 41 Corbier Crane 80 Island 80 85 21 34 PLEISTOCENE 27 Th,U 61 43b U,fel,REE, 30 Traves 10 Falkner 71 Bernyk 45 38 59 37 65 37 25 75 37 65 78 56 75 31 Intermediate to Felsic Rocks 4 Mafic Rocks : MAP P.3551 Lake, stream and swamp deposits 10 Hamer Lake 35 fel, 28 47b uW 984, kK 985 ± 40 73 mK 995 ± 60 35 RECENT bK 839 ± 80, uW 976, 50 mK 940 ± 60 61 QUATERNARY kK 761 ± 70 45 47b 75 30 56 70 zU 1163 ± 3 47 Umbrella 65 45 69 33a 67 54 25 U,fel 27 REE,U 35 mA 860 ± 3 Ce,Si, 23 fel Multicomponent layered gneiss and migmatite, minor Armer Bay Gneiss Association (units 34 and 35) CENOZOIC Lake 20 Mo, Intermediate to Mafic Migmatitic Rocks 5 Parry Sound Domain (basal) (units 30 to 35) 37 Roberts fel Th,Nb 72 25 47 Lake 48 80 30 52 15 25 75 56 40 70 71 80 54a Ch 07 37 45 52 54a 54 Au 20 48 Lake Kingshott 62 45 55 25 45 62 70 60 75 65 80 65 McEachern Key Harbour Gneiss Association (units 2 to 5) LOCATED WITHIN PARRY SOUND SHEAR ZONE amphibolite 5011000m 27 fel,REE, THRUST CONTACT WITH PARRY SOUND DOMAIN (BASAL), 45°15´00 400 50 57 10 abc 32 30 64 70 17 77 Lake 70 64 30 37 70 50 60 Cu,Ni 70 Clear 42 Island 37 82 Lake 36a 61 Lent 31 52 35 47a 37 60 Spider 39 48 80 35 Cu Zn,Cu SM,gt, 37 74 40 Zn,Mo, 65 50 70 Ag,Cu, 53 22 60 34 Au,Cu,SM 61 80 45 20 42 08 Fe,Ni 70 55 52 50 25 48 37 40 65 599000m 98 PHANEROZOIC 85 Lake 22 82 42 68 34 24 75 48a 70 75 FOLEY TP 80 40 Lake 41 39 66 70 25 26 58 38 59 53 Lake COWPER TP 42 47 35 25 Salmon Lake 40 39 36a 37 41 39 80 25 Ansley 31 75 50 47 67 32 26 Hooton Oak Lake Blackstone 11 80 One Island 47 45 40 22 Island 32 62 39 33 Peak 46 Boyd 41 41 74 Island 75 13 24 72 09 47 55 Louisa 75 Ni 19 32 50 59 Spider Lake 35 34 39 56 45 33a 65 28 55 25 45 Island 45 70 45 29 37 Derbyshire 33a 34 Ni 92 LEGEND 79°43´33 45´ 97 96 95 94 93 45 50 30 39 ke 56 55 54 a 53 91 590000m 89 88 87 86 84 83 82 81 580000m 79 L 20´ 80°00´00 78 77 76 75 74 r 52 51 71 570000m 69 68 67 66 73 72 River ne to ks 550000m 65 05´ B lac 80°22´32 15´ 10´ 50´ 96 97 98 45´ 99 600000m 79°43´29 It is recommended that reference to this map be made in the following form: Culshaw, N.G., Corrigan, D., Ketchum, J.W.F., Wallace, P. and Wodicka, N. 2004. Precambrian geology, Sans Souci area; Ontario Geological Survey, Preliminary Map P.3551, scale 1:50 000. 60 7 50 Inlet 15 13 20 eb es h 55 13 40 40 16 14 62 52 30 17 25 McCoy 42 Island 34 44 Osawa 14 30 15 16 20 4 McCoy Island Southwest Island 10 69 9 52b Islands 75 Twin 13 90 14 41 55 77 76 7 27 10 9 10 15 20 62 23 55 30 9 2 22 11 40 77 87 5 6 45 62 5 15 72 LIMESTONE 60 38 7 ISLANDS 12 13 St ls 25´ PROVINCIAL 56 22 NATURE 10 12 North Limestone Island 44 46 10 49 27 5 10 18 52b 15 34 15 7 8 50 44 30 11 Island 20 4 Beaver 20 68 10 65 52 10 72 51 22a 89 33 54a 36 Island 50 l e 76 Island n 25 20 19b 15 Limestone Islands 26 Boucher 20 20 56 LIMESTONE 19a Lake 70 60 40 45 Wallis Stalker Rocks 30 9 RESERVE 15 Snug Snug 45 52b 15 U,Si,ap 12 B li n 35 40 o 23 d B ll 19b in s B 18 20 15 25 24 20 80 7 Spectacle Islands 6 70 Snug 11 9 9 5 Haven 23 19a 24 55 13 53 55 38 19b 23 23 9 60 18 7 15 22 Gowar 4 67 12 22 Parry Is la 23 20 n d 24 Pleasant Island 44 43 21 28 38 20 50b 28 31 5020000m Snake 35 53 17 23 12 18 Georgian Bay 21 9 19a 71 18 60 15 74 Painkiller 48 57 31 8 33a 38 35 69 40 40 23 22a 19b 11 24 60 45 72 62 21a Cathcart 70 50 23 62 62 33a 56 80 45 45 24 45 40 mA 905 ± 3 70 80 30 72 54 14 82 62 48 U Ingersoll 85 Stapley 30 Island 33a Island 44 53 30 70 78 33a 40 70 Parry Island Bay 20 33a 60 85 50 70 12 70 63 85 65 65 80 31 68 29 30 Island 46 17 20 Narrows 40 26 37 39 85 33a 35 60 80°33´38 535000m 36 37 38 540000m 39 30´ 41 43 44 45 25´ 46 47 48 49 550000m 51 52 20´ 53 54 55 56 57 58 560000m 61 62 63 64 65 10´ 66 67 68 63 39 gt,Mo, 35 570000m 65 16 66 82 39 45 45 57 70 34 75 Lake 40 71 72 05´ 74 75 76 77 78 79 80°00´00 580000m 81 82 35 50 84 85 55´ 87 Orrville Parry Sound 11 35 Dorset Port Sydney 141 BAY Tobermory Dwight 60 Huntsville 117 Sans Souci Dyer's Bay Baysville MacTier 6 P.3551 118 400 Bala Lion's 118 Bracebridge 169 Edenhurst Purple Valley LAKE Penetanguishene 45° unknown generation, Fold axis; minor fold, trend only, limbs dip z-asymmetry in opposite directions (with plunge) Synform, interpreted; Fold axis; minor fold, unknown generation, m-asymmetry trend only, limbs dip (with plunge) in opposite directions Gravenhurst P.3552 Red Bay Washago 12 Wiarton HURON Antiform, interpreted; Honey Harbour 81° Nottawasaga Bay Leith Shallow Midland 11 80° 169 79° Orillia 12 48 Brechin 26 1 cm equals 25 km Location Map SOURCES OF INFORMATION Thematic information on this map is tied to a digital base map derived from maps 41 H/7 & 41 H/8, and 31 E/5 of the National Topographic Geological contact Mineral occurrences, (interpreted) prospects, discretionary Limit of mapping; occurrences (as denotes limits of area classed by the mapped during this Mineral Deposit survey Inventory (MDI)) System, scale 1:50 000. Universal Transverse Mercator (UTM) co-ordinates are in North American Datum 1983 (NAD83), Zone 17. Geological Survey of Canada Ontario Department of Mines 1953. Aeromagnetics, Seguin Falls; Geological Survey of Canada Ontario Department of Mines, Geophysical Map 127G, scale 1:63 360. Geological Survey of Canada Ontario Department of Mines 1965. Boundary of local to Location of isotopic bA 978 ± 6 extensive retrogression of granulite-facies mineral assemblages to amphibolite-facies mineral assemblages; age determination ornamentation is on the lower grade (amphibolite-facies) side (south) Aeromagnetics, Parry Sound; Geological Survey of Canada Ontario Department of Mines, Geophysical Map 1496G, scale 1:63 360. Ontario Geological Survey 2002. Mineral Deposit Inventory Version 2 (MDI2) October 2002 Release; Ontario Geological Survey, Digital Data. Bussy, F., Krogh, T.E., Klemens, W.P. and Schwerdtner, W.M. 1995. Tectonic and metamorphic events in the westernmost Grenville Province, central Ontario: new results from high-precision U-Pb zircon geochronology; Canadian Journal of Earth Sciences, v.32, p.660-671. Connare, K.M. and McNutt, R.H. 1985. Rb-Sr geochronology of the Nobel gneiss and McKellar gneiss, Parry Sound region, Ontario; in Current Research, Part A, Geological Survey of Canada, Paper 85-1A, p.175-180. ABBREVIATIONS Cosca, M.A. 1989. Cooling and inferred uplift/erosion history of the Grenville orogen, Ontario: constraints from Argon-40/Argon-39; unpublished PhD thesis, University of Michigan, Ann Arbor, Michigan, ap .............................................................apatite 223p. Al .........................................................aluminum Culshaw, N.G., Corrigan, D., Drage, J. and Wallace, P. 1988. Georgian Au.................................................................gold Bay geological synthesis: Key Harbour to Dillon, Grenville Province of clay ...............................................................clay Ontario; in Current Research, Part C, Geological Survey of Canada, Co..............................................................cobalt Paper 88-1C, p.129-133. Cu.............................................................copper 40 39 post-tectonic cooling in the Britt domain of the Grenville Province, 18a Pink to grey leucocratic gneiss gt ...............................................................garnet Ontario; Earth and Planetary Science Letters, v.105, p.405-415. 18b Pink to grey, migmatitic leucogranite to granodiorite mb ............................................................marble Ar/ Ar study of mica .............................................................mica Ketchum, J.W.F., Heaman, L.M., Krogh, T.E., Culshaw, N.G. and Intermediate to Felsic Rocks Mo...................................................molybdenum Jamieson, R.A. 1998. Timing and thermal influence of late orogenic 17a Unclassified granitoid orthogneiss Nb...........................................................niobium extension in the lower crust: a U-Pb geochronological study from the 17b Monzonitic to granitic orthogneiss Ni ...............................................................nickel southwest Grenville orogen, Canada; Precambrian Research, v.89, peat p.25-45. ............................................................peat Mafic Rocks Si.................................................................silica Mafic orthogneiss SM...................................sulphide mineralization Ketchum, J.W.F. and Krogh, T.E. 1997. U-Pb constraints on high- St an .......................................stone, anorthosite pressure metamorphism in the Central Gneiss Belt, southwestern Metasedimentary Rocks St gb..............................................stone, gabbro Grenville orogen; Geological Association of CanadaMineralogical 15a Unclassified paragneiss St gn...............................................stone, gneiss Association of Canada, Programs with Abstracts, v.22, p.A-78. 15b Marble; may be associated with rusty graphitic schist St gr...............................................stone, granite 15c Calc-silicate gneiss St ls ...........................................stone, limestone Krogh, T.E. and Davis, G.L. 1969. Geochronology of the Grenville St mb .............................................stone, marble Province; Carnegie Institution of Washington, Yearbook 67, p.224-230. Ti.............................................................titanium U.............................................................uranium Reynolds, P.H., Culshaw, N.G., Jamieson, R.A., Grant, S.L. and Zn..................................................................zinc McKenzie, K. 1995. 40 39 Ar/ Ar traverse - Grenville Front Tectonic Zone bA = biotite Ar/Ar date, in Ma Metamorphic Geology, v.13, p.209-221. Thermobarometry, geochronology and the interpretation of P-T-t data tU = titanite U/Pb date, in Ma in the Britt domain, Ontario Grenville orogen, Canada; Journal of Intermediate to Felsic Rocks Grey, migmatitic, leucocratic hornblende-biotite orthogneiss zU = zircon U/Pb date, in Ma Petrology, v.33, p.1225-1259. 43a Pink, sugary, layered leucocratic gneiss of granodioritic to monzodioritic composition 43b Grey biotite leucogneiss of granodioritic composition van Breemen, O., Davidson, A., Loveridge, W.D. and Sullivan, R.D. Migmatitic Rocks 1986. U-Pb zircon geochronology of Grenvillian tectonites, granulites Mafic Rocks Grey, leucocratic, migmatitic hornblende-biotite-garnet and igneous precursors, Parry Sound, Ontario; in The Grenville Amphibolite orthogneiss of tonalitic to granodioritic composition Province, Geological Association of Canada, Special Paper 31, p.191- 12 Metasedimentary Rocks Unclassified paragneiss 43a 37 13 Lake Wodicka, N., Parrish, R.R. and Jamieson, R.A. 1996. The Parry Sound 36 35 16 37 48 26 400 Tucker Magnetic declination approximately 10°36'W in 2004. Felsic Rocks 10 Metasedimentary Rocks Rusty weathering, graphitic paragneiss Geology not tied to surveyed lines. Metasedimentary Rocks Metric conversion factor: Intermediate to Felsic Granulites Unsubdivided, grey to buff weathering, orthopyroxene- 9 bearing intermediate (granodiorite, tonalite to diorite) Grey, migmatitic, leucocratic garnet-biotite paragneiss, orthogneiss locally with sillimanite; pink leucosome, may contain garnet, CONGER TP 47 5012000m 38 40 35 15 66 Bayfield Gneiss Association (units 6 to 8) 590000m 91 50´ CREDITS Intermediate to Felsic Granulites (retrogressed) Intermediate to Felsic Rocks Pink, sugary leucocratic gneiss Unsubdivided, grey, foliated to gneissic, intermediate 7 Intermediate to Felsic Intrusive Rocks 7a Unsubdivided grey and pink, variably layered, highly strained orthogneiss, in places with recrystallized 7b Mafic Rocks Grey, leucocratic, migmatitic hornblende-biotite-garnet orthogneiss of tonalitic to granodioritic composition Unsubdivided, layered, predominantly mafic two-pyroxene Metasedimentary Rocks Metasedimentary Rocks 6a Grey, leuco- to mesocratic garnet-biotite paragneiss, 36a Layered paragneiss, garnet-rich granulite commonly with sillimanite; locally graphitic and 36b Marble, calc-silicate tectonic breccia rusty weathering Calc-silicate and amphibolite gneiss associated with garnet-biotite paragneiss of unit 6a Geology by N.G. Culshaw, D. Corrigan, J.W.F. Ketchum, P. Wallace and N. Wodicka, 1987 to 1990. Geological compilation by N.G. Culshaw, 1991 and 2004. Digital drafting by S. Josey. Geology, legend and mineral deposit information reviewed by R.M. Easton. Cartographic production by S. MacLean. To enable the rapid dissemination of information, this map has not received a technical edit. Discrepancies may occur for which the Ontario Ministry of Northern Development and Mines does not assume liability. Users should verify critical information. Issued 2004. Information from this publication may be quoted if credit is given. 45°15´00 89 1 foot = 0.3048 m. Intermediate to Felsic Granulites (layered) 6b Lake geochronology; Canadian Journal of Earth Sciences, v.33, p.1087-1104. Pink, layered, leucocratic paragneiss granulite or gneissic metagabbro 70 66 88 11 Metasedimentary Rocks potassium feldspar megacrysts 17 86 Nobel Culshaw, N., Reynolds, P.H. and Check, G. 1991. A 60 Clear 55 40 53 83 Novar Broadbent Migmatitic Rocks evidence of retrogression from a granulite facies precursor 60 50 73 56 50 30 GEORGIAN Kearney Sprucedale McKellar 69 Waubamik Dillon hA = hornblende Ar/Ar date, in Ma 6 82 27 25 Baril Station Tuccillo, M.E., Mezger, K., Essene, E.J. and van der Pluijm, B.A. 1992. (granodiorite, tonalite to diorite) orthogneiss containing 38 37 60 42 Lake 49 Dunchurch wR = whole rock Rb/Sr date, in Ma 60 60 U 38 14 13 40 50 35 Lake Lake Sovereign 81 43b 75 Salmon only (with plunge) 35 Magnetawan Burk's Falls Ardbeg fel............................................................feldspar Britt Domain (units 1 to 14) 8 30 Forget Fold axis; minor fold, s-asymmetry 35 Ahmic Harbour Inlet Fe..................................................................iron (e.g., unit 39 or 40); pegmatite veins may be common 75 50 35 37 Lake Third 41 43 45 34 50 interpreted; trend 35 Byng to Britt Domain, Grenville Province, Ontario, Canada; Journal of Unsubdivided, buff to grey weathering, layered, feldspathic 35 Second 60 16 75 South River Sundridge Magnetawan Felsic Rocks granulite 40 40 85 HUMPHREY TP 37 54 Long Arm Port Loring North mA = muscovite Ar/Ar date, in Ma 55 Road 38 61 37 Nb 75 62 45 65 86 Pakesley P.3548 Britt muscovite, magnetite 37 30 60 37 51 15 39 69 40 65 35 40 Road Lineament, Grey hornblende-epidote-biotite tonalitic orthogneiss PARAUTOCHTHON NORTH OF PARRY SOUND DOMAIN 37 37 34 70 76 70 43 49 64 mb Hayes Corners 42 25 Rosseau Black Cu 73 21 70 35 85 56 37 37 48 30 75 40 80 75 24 41 36 44 SM,Au 8 85 38 First 65 Key Commanda 45° Grey, migmatitic, tonalitic to granodioritic gneiss with Quartzite Buff to pink weathering, leucocratic granulite 45 75 72 39 61 12 53 40 16 40 40 Lake 85 55 72 Interlayered amphibolite, semi-pelitic gneiss and 46° Pickerel 207. 52 fel Cu,SM,Ni Lake 13 81 40 Scime 70 45 44c Parry Sound Domain (interior) (units 36 to 41) 37 30 80 75 79 50 72 Amphibolite TECTONIC CONTACT WITH SUBJACENT 68 70 27 Lake Grey metatextite with pink, hornblende-epidote-bearing 17 Lake 41 44 80 45 74 19a Fossmill domain: a far-traveled allochthon? New evidence from U-Pb zircon Windfall Cu,SM,Ni 36 16 80 Cu,Mo,SM Legged 36a Lake 55 41 Lake 21 Rankin 63 67 11 47 45 65 55 85 36a 39 80 Mafic orthogneiss 44b 80 80 55 30 Lake 80 80 57 59 67 74 80 15 Migmatitic Rocks BASE OF LOWER GO HOME DOMAIN NOT OBSERVED PARRY SOUND DOMAIN (INTERIOR) 3 86 78 45 75 SM 37 69 Spider 46 30 55 59 15´ Lake 39 44 5011000m 42 57 39 Ni Vicary 29 30 74 15 Three 44a 38 80 40 34 15 Mafic and Metasedimentary Rocks 57 75 Lake Otter Lake 75 85 85 85 33 54 40 74 30 43 52 Creswicke Lake 76 45°15´00 40 Westphal Cu,Au,Ag 30 80 39 10 57 41 47a 74 35 50 65 30 Lake Cu,Ni Seven Mile 16 77 80 85 16 26 62 25 Lake 25 25 45 48 44 30 25 7 th ou el nn ha C Island 27 41 Good Cheer 50 65 31 34 29 35 14 S 35 PROVINCIAL PARK 18 Intermediate to Felsic Rocks 35 64 62 75 42 27 23 60 60 Blue 40 30 Cu 40 34 COWPER TP Otter Lake 9 17 33 Canoe Lake Horseshoe Falding 40 THE MASSASAUGA 33 37 McLaren 39 52 43 72 88 65 49 49 30 20 20 Armer Bay 33 34 62 49 McCoy Lake 38 44 24 Five 67 47a 27 20 23 Cu 52 30 25 40 25 Islands 11 Cu 39 Grey, migmatitic layered gneiss 7 Wright 75 Unsubdivided pink and grey leucocratic gneiss Honey Harbour Gneiss Association (units 15 to 18) 14 18 41 s Cre e k 40 84 60 68 60 82 39 39 Mile 22 37 45 17 Martyr 47a n 86 31 45 Otter Lake 55 Lake Cu 44 37 35 Island 45 46 40 5 20 Island 80 70 56 St an 33 50a Hulett 50 31 17 50a 48 70 ha C Ha in e 45 45 Holmur 50 39 Jack Lake Dunroe Bay Island 80 34 57 th 34 55 Murdock Long Lake 46 Lioness 69 Dockmure 31 44 33 13 u So n l e Intermediate to Felsic Rocks PARAUTOCHTHON SOUTH OF PARRY SOUND DOMAIN 13 71 60 55 60 Fe,Ti,SM Lake 49 75 45 30 Co,Cu,SM 53 22 57 54 Sandy 71 35 Underhill 57 57 Lipscombe 30 30 Quartzite Nadeau Island Gneiss Association (units 9 to 14) Lake Lake 64 21e Blackstone Lake Gneiss Association (units 42 and 43) Lake 45 McDonald Linger 19 Para-amphibolite Kiosk 79° Powassan Restoule Ag................................................................silver Horseshoe Back Lake 30 Cu 10 29 70 44 70 65 69 46b 40 40 84 Bennett Lake Lake 24 49 21d ALLOCHTHON-PARAUTOCHTHON BOUNDARY Grey, migmatitic tonalite to granodiorite orthogneiss Brennan 400 65 84 72 Sanagan 25 Isabella FOLEY TP 78 51 46 40 82 r 68 27 47a zU 1377 ± 14 78 47a e Island zU 1160 60 43 zU 1382 ± 30 C n 45 Virtue Lake Lake Cu 65 25 e iv Fe,Ti 7 34 78 50 70 45 65 ee in n ha 70 34 82 84 23 43 Island 60 65 n R 50a l 80 80 35 37 72 n y e 85 33 80 Waubun o 25 32 45 70 55 35 81 57 o B 15 St an 35 33a 60 65 66 33a 45 Island 15 79 m o Three Mile Lake 50 Nash 70 35 43 33a 65 75 50 33 55 45 45 Pink, sugary, layered leucocratic gneiss quartzite PARK 69 84 35 75 64 43 65 60 68 32 14 65 55 62 22a 55 19a 65 76 40 48 Lake 46a 44d PROVINCIAL 50 63 55 St mb 44 15 St gb 55 80 30 Calc-silicate gneiss 80° Noëlville Head (NADEAU ISLAND GNEISS ASSOCIATION): Felsic to Intermediate, Layered or Migmatitic Rocks Lake OASTLER Rintoul 48 Victoria Island 34 R iver LAKE Point 2 33 60 Bo y ne 61 48 Rose St an, 30 50 70 45 33a el 40 16 32 70 89 r Yarrow 33 27 15 iv e 19 40 47a 35 66 70 85 18 70 65 ann 14 bA 1126 ± 2 30 54 22 80 58 Ch 12 81 70 mA 909 ± 3 31 FIRST NATION I.R. Al Island 33b 58 19a 33a 84 70 50 Parry Island Palestine 63 62 33a 70 22a 33 PARRY ISLAND Parry Island 49 78 37 Island gt,mica 84 47a 47 50 31 68 31 50 40 82 10 75 57 47 Bateau 32 69 80 68 62 85 Oastler Lake 83 71 35 17 57 63 zU <1385 ± 4 80 75 19a 76 70 45 59 71 71 80 Depot Harbour Lake 37 29 31 83 33a 39 Depot Island 45 46 5020000m Cu trend only, teeth on subhorizontal) TECTONIC CONTACT WITH SUBJACENT BRITT DOMAIN 16 Lake Cochrane 66 28 17 Pink to grey marble 21c Small outcrops of unit 47a or 47b hosted by adjacent Flaxman Cu,fel Cu,Au 34 75 45 39 Medium to dark grey, biotite-rich quartz-plagioclase 21b 19c Moon River Gneiss Association (units 44 to 46) 20´ St mb 65 67 Lake Lake McNutt thrust, interpreted; (trend only, inclined) varied amounts of pink leucosome Moon River Subdomain (units 42 to 46) 21 Liebeck Lake Lake 400 35 88 35 70 67 74 Haines 30 78 35 21a 19b 17 Cu,Ag, mb 80 Metasedimentary Rocks LATE PALEOPROTEROZOIC 22 South Parry 85 46 68 48 41 31 21 31 mica Sound 75 Weakly foliated to gneissic, mafic intrusive complex INTRUSIVE CONTACT Lake gt 51 50 Dark grey dioritic orthogneiss, possible hypabyssal Alban Rosseau leucosome ALLOCHTHON Lake 82 39 75 47b McGowan 60 85 37 47 Depot 43 40 Lake Island mb,fel, 31 31 33a Pell 79 46 35 9 mA 891 ± 8 Harbour 28 23 25 44 45 50 31 62 el se Island Cha nn Ro 49 43 25 31 39 37 83 66 Parry Island Bay Spectacle Lake Richmond Parry Hay 70 19 EARLY MESOPROTEROZOIC to Capton Harbour 50 58 36 40 67 20 34 28 37 40 29 54 Anorthosite, gabbroic anorthosite, minor gabbro Mohan Lake Zn,Au,gt 45 21e 55 68 46 22b tectonostratigraphic boundaries) (indicated by triangles) Lovell 55 mb 30 35 47a Lake 20 34 34 50a Small outcrops of unit 48a or 48b hosted by adjacent country rock units (commonly found along 55 30 31 36 22 33a 31 79 Islands 28 41 41 Nias 24 41 Rose 40 Reid Islands 34 37 43 48c 47c Lake 24 75 31 41 70 45 60 33 20 Lake 27 25 Island 45 31 48 24 23 40 11 30 47 43 20 33 24 67 Island 41 54 48 6 19 23 Lane 36b 35 35 24 29 Islands 50a Weakly foliated to gneissic metagabbro, primary Hornblende diorite, gabbro St gn St mb 35 10 21 23 46 54b 23 Long 39 g 35 25 Grey tonalitic orthogneiss Lower Go Home Domain (units 15 to 18) 40 40 37 30 30 Sister 65 19a 12 18 Shoal 48 24 21a 29 McLean 28 52a 24 60 9 60 Sound 25 15 5 24 48 40 Spruce 10 10 56 15 Island 9 16 15 29 Island 14 50b 19 13 Pancakes 15 21 Davy Island 20 19 19a 26 20´ 10 Parry 26 31 26 13 S Channel 10 21b 8 65 The P arry Sound 10 41 23 19 12 10 14 78 9 15 29 e 15 19 5 3 S 44 38 50 15 14 10 30 60 Lake Faris 36 22a Ojibway Gneiss Association (units 19 and 20) consisting of gabbro, anorthosite and ultramafic rocks Lake 21 19a 22 Unit 50a, with associated pink granite and grey 48b Haines 5 35 15 Weakly foliated to gneissic, grey hornblende-biotite Mafic Intrusive Rocks, Anorthosite Suite 39 Cu 25 30 12 11 23 47a 40 M e is 4 25 Intermediate Rocks horizons Martin Lake Lake St gn 15 16 St. Aubyn Bay 20 St gr 5 Development Agreement (COMDA), a subsidiary agreement to the Economic and Regional Development P.3550 hanging-wall side Pink, migmatitic, sugary leucocratic gneiss and subordinate paragneiss and schist ("Dillon schist") with quartzite country rock units (indicated by dots) 47 15 North 10 w 21c 50 zU 1114 ± 2 24 Lake Neville 20 30 23 18 Heaslip 16 16 Lake St gn Nb,U 22 21 igneous texture commonly preserved Carruthers Mill Lake clay 5 45 21a 16 e K 18 Island 11 6 20 zU 1159 ± 5 St gn PARK Bay 31 Unit 51a, with associated granite and monzonite Intermediate Intrusive Rocks 48a 52a 20 hanging-wall side Lineation (with plunge, Felsic Rocks intrusion (circa 1450 Ma) Mafic Intrusive Rocks 48 Standing Lake 20 15 16 19a 47a Lake 13 29 20 PROVINCIAL 23 35 Darlington's U 30 24 23 KILLBEAR Park mA 889 ± 3 McLean Lake 35 Wall 35 9 Killbear 21d 13 22 28 Home Lake trend only, teeth on Foliation 35 Grey, layered quartzofeldspathic gneiss containing Weakly foliated to gneissic, pink monzonite, minor granodiorite and monzodiorite 25 40 Thrust fault, interpreted; Allochthon boundary Intermediate to Felsic Rocks grey, migmatitic leucogneiss Weakly foliated to gneissic, grey tonalite with associated 30 50a 48a Ouimet Point 13 U,Nb 53 25 15 73 57 17 16 49 CHRISTIE TP Lake 5 14 22 12 23 8 50 32 21a Lake 10 40 St gr 20 23 granodiorite Dell 25 the five-year Canada Ontario 1985 Mineral Pointe au unknown generation Grey, migmatitic tonalitic and granodioritic orthogneiss hornblende, biotite, epidote minor tonalite 50b 35 St gn 24 granodiorite, locally potassium feldspar megacrystic, 26 36 45 Bay Geological Synthesis, funded as part of P.3549 foliation; Intermediate to Felsic Rocks Dainty 69 St gn mapping program, Project C.2.3, Georgian Killarney trend only parallel tectonic Felsic Rocks Intermediate to Felsic Intrusive Rocks 50a Frey 12 25 Mapping was conducted as part of a three-year 46° Fault, interpreted; layering and/or 35 Felsic to Intermediate Intrusive Rocks 47a 34 10 12 12 15 Mowat Island 25 23 26 21 St gn 6 35 12 9 15 12 49 26 Island 23 4 20 4 Unit 52a, strongly foliated to protomylonitic Lake McGruther Lake 45 30 Bay 25 10 16 Compositional ALLOCHTHON-PARAUTOCHTHON BOUNDARY syenite 50 zU 1350 ± 50 Bowers 37 52c 51a 20 50a St gn 21e 15 20 47 36 7 16 Unit 52a, with associated granite and quartz monzonite, 27 39 U 12 18 22b 20 14 25 Pink, leucocratic granite, locally potassium feldspar 52b 51b 20 21a Geological Survey. Harbour Layered to podiform calc-silicate gneiss 25 28 23 15 24 18 70 21d Gilboe Lake Lake Lake 20 17 15 37 19 124 wR 1330 ± 44 21 Avis 51 20 25 24 78 19b 21a ay 50 St gn 53 58 Horse Island 24 a y 30 75 53 5 30 24 13 C 32 21d 17 46 12 wR 1145 15 13 23 40 60 60 70 Harbour 15 Island 39 66 60 70 19a 35 40 67 18 Bay 13 8 30 20 SYMBOLS Metasedimentary Rocks TECTONIC CONTACT WITH SUBJACENT LOWER GO HOME DOMAIN: Santa Lake Cramadog 35 40 Island 23 Loon 32 45 21a 21 25 megacrystic 28 Martini Lake 20 47a This map is published with the permission of the Director, Ontario Trout Creek Pink, sugary leucocratic granite gneiss Felsic Intrusive Rocks 52a er Riv 10 45 25 Elizabeth 25 30 8 zU 1346 ± 69 54 15 50 14 60 23 20 54a Island 75 37 75 15 NATURE 20 25 52a 50 23 21 12 23 8 80 29 Island 26 commonly potassium feldspar megacrystic mA 884 ± 10 Island 32 20 70 52 PROVINCIAL 46 30 11 7 70 50 19 29 33 38 Grave 13 40 Huckleberry Island 19 31 70 9 1 47 22a 27 Lake Corners 31 20 Mafic orthogneiss, amphibolite COMMONLY CONTAINING GARNET 52 2 km NTS Reference: 41 H/7 & 41 H/8, 31 E/5 French River Mafic Intrusive Rocks, Coronitic Metagabbro Suite DEFORMED AND MIGMATITIC ORTHOGNEISS, Seq uin 20 20 21 15 28 vertical) (circa 1165 Ma) 1 69 Mafic Rocks "SINGLE CYCLE PLUTONIC ROCKS", VARIABLY 29 Basin 22 Goat 29 McDOUGALL TP 47a Portage Lake Mountain 12 16 24 20 10 30 7 32 25 38 21d 79 32 60 23 25 52b Mink 5 Lily 54a ISLANDS 25 28 Island 62 79 10 16 23 South 15 19b 15 40 22 40 41 21a 20 54 n Green 25 27 Franklin 70 20 St gn 0 Agreement (ERDA) signed by the governments of Canada and Ontario. Grey, migmatitic tonalitic and granodioritic orthogneiss Sand Bay Gneiss Association (units 21 to 24) Badger's 14 16 15 13 12 46 correspond to a suite or a complex. Grey, heterogeneous, leucosome-rich (>25%), INTRUSIVE CONTACT Isabella mA 903 ± 3 23 35 16 32 a h C 9 23 65 7 Bay 40 73 24 9 29a 29b Lake St gn 67 24 36 30 20 If it were decided to 1983 North American Stratigraphic Code, in most cases, they would (trend only, inclined, Pepper Lake 35 Carling metamorphism or intrusion of mafic dikes. Intermediate to Felsic Rocks coarse-grained, locally ophitic textured, metagabbro Carling 25 23 60 65 U 10 gneiss association is an informal stratigraphic term, introduced by Culshaw et al. (1988), that is primarily based on rock type, but which formally name a "gneiss association" as a lithodemic unit under the Dark green to black, weakly foliated to gneissic, medium- to Lake 35 ek Thus, not all map units in the legend may appear on the map face. A Shawanaga Domain (units 19 to 24) 80 37 20 40 25´ Funston U 36 21a 65 30 Greer 20 54 35 18 53 5030000m 19b 40 15 Cr e Maps P.3548, P.3549, P.3550, P.3551 and P.3552. and slivers Lake Nobel 35 15 37 21a 45 30 10 laboratory investigations, including petrography and geochemistry. This is a legend common to Ontario Geological Survey Preliminary also may contain information with respect to plutonic history, Lake 23 tU 1058 ± 2 1000 m © Unit 54a, with associated anorthosite and gabbro pods 19b 46 30 Lake 55 10 70 L ake 52a 6 40 Grey biotite-muscovite-garnet-kyanite gneiss and schist Weakly foliated to gneissic mafic rocks of unknown facies metamorphism and variably retrogressed 21e Blair 35 32 55 es Straight and mylonitic gneiss derived from units 1a This legend is a field legend that locally incorporates the results of Pere Brebeuf Gneiss Association (units 25 and 26) protolith and of varied age, subjected to eclogite Lake Bell 10 28 52 60 20 17 56 5 5 21d 35 ng 36 28 30 50 75 60 54a Ardagh 21a h 5 32 23 m 19b 18 39 54a 54b 36 40 Cole Lake 16 20 16 23 mA 899 ± 6 20 15 21a 21a 10 37 S 26 28 11 Island 70 ko e sh e b 19 36 Raper 2 40 30 40 21a 80 9 50 45 im 23 10 15 21d 8 e 22 35 5 52b 12 75 28 35 23 30 8 10 30 23 S a c Mafic Rocks 31 Blackwater 15 18 80 30 10 76 76 39 55 52b 84 60 20 18 4 15 5 36 39 56 4 55 66 18 47 18 53 80 4 7 35 38 25 R 30 5 60 60 60 56 63 9 52 67 5 6 57 g Trout 47a Shebeshekong 32 60 21a 75 40 36 19b Island 70 42 85 23 19b 30 30 21b 44 70 Edgar 14 hA 969 ± 5 38 43 RESERVE 29 bA 943 ± 5 40 Island 41 55 70 Elmtree 34 11 14 10 10 Metasedimentary Rocks 35 54 5 10 20 20 7 34 37 45 15 21a 45 20 41 55 ko n r e 5030000m 30 45 54 70 60 28 85 39 38 55 60 19b 15 HIGH-GRADE METAMORPHISM WITHIN THE GRENVILLE PROVINCE Lake 15 No Unit 1a, with minor amounts of unsubdivided polycyclic and/or 1b LOCATED WITHIN THE PARRY SOUND SHEAR ZONE 29 MESOPROTEROZOIC 32 tr 35 19b 1c b Boy 45 15 25 le Shebe s he Litt 21d S 11 1b migmatitic granodioritic gneiss Hurdville 20 15 559 40 10 iv 18 Dillon 25 23 70 20 15 20 35 21e 2 4 PARRY SOUND AREA 81° 40 21 17 30 INTRUSIVE CONTACT 35 5 37 72 10 28 35 35 45 55 1 Adanac 21a 25 13 23 30 33 61 15 58 23 55 20 85 75 80 53 30 Shebeshekong 12 Landing 21b 43 5 Brooks 23 72 17 ek re 14 42 31 21a 72 45 65 7 62 6 53 52b Lake MAP P.3550 Queen's Printer for Ontario, 2004. Brown weathering, fine- to medium-grained diabase 47a C 14 19b 16 52 leucosome older than the dikes is observed Gneiss Association (unit 30) 40 45 43 metamorphosed mafic dikes (amphibolite). pelitic and garnet-rich gneiss interlayered with bA 926 ± 4 30 Para-amphibolite and unsubdivided paragneiss; includes Gneissic Rocks Structurally Below the Lighthouse (590 Ma) Lake mA 897 ± 4 ir 53 Cu 43 70 Mostly medium-grained, moderately foliated to gneissic, migmatitic, granodiorite to tonalite containing Mafic Intrusive Rocks (Grenville diabase dike swarm) 55 33 1a Mafic and Metasedimentary Rocks Pine Island Gneiss Association (units 27 to 29) Johnston Intermediate Migmatitic Rocks 1 and metasedimentary gneiss PRECAMBRIAN 39 5 30 20 75 35 15 peat CARLING TP Sand Bay 83 24 30 27 13 Amphibolite grey to white sublithographic to lithographic limestone) Ontario Geological Survey Scale 1:50 000 Mafic Rocks quartzofeldspathic gneiss and minor quartzite Broadbent 23 20 Quartzite, minor associated paragneiss NEOPROTEROZOIC la 20 6 19 21a 11 40 19 sillimanite gneiss; minor quartzite, calc-silicate gneiss Unsubdivided: includes Gull River Formation (light brown- 34 Waubamik 12 15 36 locally with garnet-hornblende and garnet-kyanite and grey to blue-grey interbedded limestone and dolostone, : PRECAMBRIAN GEOLOGY granodiorite orthogneiss Upper Go Home Domain (units 25 to 29) 23 19b Mafic monzodiorite gneiss Layered, pink to grey quartz-feldspar-biotite paragneiss, TECTONIC CONTACT (SUSPECT) WITH THE SHAWANAGA DOMAIN, Mile Spectacle Lake 15 30 14 14 10 Nine 23 19b 20 31 Chemical Sedimentary Rocks 31 Lake 27 Mafic gneiss; minor metagabbro, anorthositic gneiss 3b Layered, migmatitic, grey tonalite, minor trondhjemite, and Shadow Lake Formation (calcareous red and green Lake 20 20 er 32 McKELLAR TP Lake 50 35 25 29 45 56 65 B 35 32 85 iv MIDDLE ORDOVICIAN Campbell Cranberry 31 19b 16 75 52a 20 30 17 R g 30 20 30 33a UNCONFORMITY 35 30 10 25 25 61 Johns mica Lake Dinner Lake 64 14 16 g 30 55 5 54 51 e sh n 9 19b 2 Sh eb 40 o k Island 16 23 40 33 70 19b 69 tU 1045 25 e Dart peat 62 60 70 12 55 73 70 20 40 15 47a 30 peat 22 38 40 47a 70 37 10 10 25 42 50b 12 60 11 14 55 18 11 in b a arkosic sandstone, pebbly sandstone, siltstone and shale) 30 12 55 7 85 35 35 35 19b 11 3a Metasedimentary Rocks 2 Intermediate to Felsic Rocks with Metadiabase Dikes ORDOVICIAN 36 r 36 50 13 9 4 80 10 40 80 52b 20 40 43 55 36 50 14 35 16 23 50 50 8 25 85 4 14 Island 14 75 82 Sisters 33 80 60 66 18 72 4 Fe w u e iv R 35 tU 1026 6 3 3 Quartzite, minor associated paragneiss and para-amphibolite Bustard Islands Gneiss Association (unit 1) PALEOZOIC Tongue Lake 23 19b 58 itouwabing L ake peat,St gr 35 17 34 Lake 65 19b 30 70 75 80 20 64 52b 60 35 36 Ma n Lake 39 69 19b Mafic Rocks 33b Harris U 21e St gn 85 75 15 33 52a mica 3 12 10 mA 888 ± 8 40 34 32 Mazur 55 25 65 80 35 34 40 18 Lockett Ri ve r 13 62 64 64 82 7 10 23 65 Lake 70 9 10 8 Lake 22 35 St gn 15 5 g 36 10 76 19b 82 82 19 Imrie 12 46 20 30 21a 6 2 11 52b 41 35 60 30 72 14 74 87 20 20 on clay 68 45 60 10 75 50a Big 23 30 10 30 19 McCoy 26 25 68 43 20 35 45 3 4 30 36 27 Island 5 5 76 6 7 11 35 Little 62 75 70 11 65 25 10 30 65 50 52b 50b 53 11 80 50 6 40 73 25 12 10 32 5 65 e Mafic and Metasedimentary Rocks UNCONFORMITY mA 894 ± 3 FERGUSON TP 20 Sh eb Predominantly grey gneiss with pink granitic leucosome Lake 25 25 50 50 22 12 60 40 20 56 63 45 60 19 75 15 and till 37 20 19b 75 50 ak e 6 1 tU 967 45 50 21 L 22 57 77 19b tU 956 45 6 30 ek on g 55 18 80 33 2 30 Pink, sugary leucocratic gneiss 4c Glacial deposits; sand and gravel, clay 57 Crow 24 Woods 45 45 31 ek 35 h 30 46 45 k 34 S 9 75 10 34 10 10 21a 23 27 15 50b 70 St an Lake 15 5 35 30 35 45 35 28 19b 24 e sh 14 21d 23 zU 1121 ± 12 19b 23 22 Redfern 5 78 L it tl e 50 24 zU 1095 Island 3 27 70 63 80 50 16 4b Lighthouse Gneiss Association (units 31 to 33) Lake e Blai r Cr Hertzberg 36 30 zU 1091 ± 11 67 40 50b 38 18 Lake 35 25 54 26 38 22 30 55 15 65 SHAWANAGA TP 20 5 83 zU 1001 ± 4 11 80 12 25 23 8 20 9 8 15 45 45 78 52b 40 19b 8 41 70 66 76 20 40 45 70 8 Shawanaga 9 5 70 49 Unsubdivided pink and grey leucocratic gneiss quartzite PLEISTOCENE Killeen Lake Mile R 75 53 Nine 25 it o zU 1042 ± 4 23 53 52b 25 Lake, stream and swamp deposits e 38 Marsh 4a Para-amphibolite, layered mafic gneiss, paragneiss and on 2 50 80 70 60 23 13 4 22 Intermediate to Felsic Rocks 4 Mafic Rocks RECENT 38 47a 52a 12 12 35 15 n zU 988 ± 2 85 55 4 St an 50 23 27 23 ck st 30 27 20 5 50b 30 40 50 QUATERNARY 35 80 35 M a 5 25 30 30 40 5 52 30 19b 6 B la t 3 21 Lake r le In 14 75 52b 11 54a 4 25 85 peat Madigans Multicomponent layered gneiss and migmatite, minor Armer Bay Gneiss Association (units 34 and 35) Vowel 47a Ri ve zU 1019 ± 4 46 20 eric 50a 42 41 50b 35 Intermediate to Mafic Migmatitic Rocks 5 Parry Sound Domain (basal) (units 30 to 35) CENOZOIC 19b g 50a Fr ed 14 70 80 Key Harbour Gneiss Association (units 2 to 5) LOCATED WITHIN PARRY SOUND SHEAR ZONE amphibolite 21e 14 Lake 51 55 4 65 8 52b 37 23 30 25 Rainy 50a 51 THRUST CONTACT WITH PARRY SOUND DOMAIN (BASAL), 5039000m ito uw ab in 54b 3 12 45 50a 50b 28 16 11 67 66 65 64 63 62 61 PHANEROZOIC Ma n 11 5038000m 23 65 19b 9 11 35 Grouse Lake 560000m 59 58 57 45°30´00 La ke 27 53 35 Island 78 56 55 e 17 21a Shawanaga 54 53 52 de 26 5 11 16 51 550000m abc 593000m 92 91 590000m 89 88 87 86 85 84 a th 40 49 48 47 46 er 45°30´00 45 44 43 83 82 81 580000m 79 78 iv 42 41 77 76 75 74 R 540000m 39 38 72 71 570000m 69 68 73 u in 37 36 535000m 20´ 25´ 30´ 80°33´38 15´ 55´ 80°00´00 05´ 10´ LEGEND 79°47´48 50´ 92 593000m 94 79°47´48 It is recommended that reference to this map be made in the following form: Culshaw, N.G., Corrigan, D., Ketchum, J.W.F., Wallace, P. and Wodicka, N. 2004. Precambrian geology, Parry Sound area; Ontario Geological Survey, Preliminary Map P.3550, scale 1:50 000. 5 56 50a 1 72 5 34 1 50a 25 31 4a 47 64 26 5 60 15 76 5 50a 20 17 58 26 57 33 50b 5 4a 84 81 62 Gi x rou R e iv r 5 70 57 20 72 62 Rocks 50b 55 58 50a 27 61 48 25 48 82 86 5060000m 40 77 39 80 1 44 70 55 Island 42 65 4b 4b 60 80 79 33 80 50b 47 85 76 80 76 58 Head Island 51 70 60 25 42 Olwyn 40 45 7b 37 40 4a 35 8 85 St gn 20 50 40 84 25 32 50a 28 7a 80 40 60 80 7b 45 10 55 N ai iv ot R sco er M h a n n 48 64 8 70 64 50 78 7a 75 ar Ch 70 78 7b 80 Burnt 70 60 40 62 61 60 61 8 10 80 60 8 25 48a 18 7b 70 7a 60 35 4 1 8 11 529A 20 8 30 Lake 66 60 67 74 Inlet 67 37 47 7b 30 43 7a 56 27 30 60 20 51 37 33 47 30 7a 30 33 38 58 25 34 32 16 14 8 23 6b 20 25 8 10 45 45 14 15 22 34 31 70 37 7b 60 8 tU 1430 ± 17 20 70 20 52b 60 20 8 40 52b 20 25 75 24 15 30 zU 1448 ± 1 85 50 12 69 70 52b 85 70 7b 23 14 55 Pointe au Baril 85 52b Lookout 10 7b 85 20 25 46 40 52b 50 10 49 13 5 14 45 5 40 5 7b 52b 60 35 37 15 25 Middle 31 Ojibway Island 5 22 55 35 80 80 Oberlin Bay 80 65 80 75 41 Bill 80 30 14 18 30 8 9 19b 40 75 40 52b 60 11 39 10 35 45 15 11 45°30´00 40´ 27 28 29 530000m 31 32 35´ 33 34 35 36 37 38 39 30´ 540000m 12 3 41 42 43 44 20 44 75 51 35 20 34 70 70 4 82 68 75 13 9 80 55 50b 46 25´ 38 Lake 4 (with plunge) occurrences 22b Dark grey dioritic orthogneiss, possible hypabyssal 9 ROUND LAKE 6 82 50a 50b 47 gU 1450 ± 1 41 PROVINCIAL Mineral Deposit (interpreted) Inventory (MDI)) Medium to dark grey, biotite-rich quartz-plagioclase Limit of mapping; Location of isotopic paragneiss and schist ("Dillon schist") with quartzite denotes limits of area horizons mapped during this 21b Pink to grey marble survey 21c Calc-silicate gneiss 21d Para-amphibolite 21e Quartzite Metasedimentary Rocks 21a 19b 51 52 20´ 11 Orrville 35 Dorset Port Sydney 141 BAY Tobermory Dwight 60 Huntsville Parry Sound 117 Sans Souci Dyer's Bay Baysville MacTier 6 P.3551 118 400 Bala Lion's 118 Bracebridge 169 45° Edenhurst Honey Harbour Purple Valley LAKE Penetanguishene Gravenhurst P.3552 Red Bay Norland Washago 12 Wiarton HURON Nottawasaga 81° Bay Leith Midland 11 80° 169 79° Orillia 12 48 Brechin 26 Location Map 1 cm equals 25 km SOURCES OF INFORMATION Thematic information on this map is tied to a digital base map derived from maps 41 H/9 and 10 of the National Topographic System, scale 1:50 000. Universal Transverse Mercator (UTM) co-ordinates are in North American Datum 1983 (NAD83), Zone 17. Geological Survey of Canada Ontario Department of Mines 1965. Aeromagnetics, Pointe-au-Baril; Geological Survey of Canada Ontario Department of Mines, Geophysical Map 1497G, scale 1:63 360. Geological Survey of Canada Ontario Department of Mines 1965. Aeromagnetics, Naiscoot River; Geological Survey of Canada Ontario (MDI2) Migmatitic Rocks gf ............................................................graphite 19a St gn ..............................................stone, gneiss Grey metatextite with pink, hornblende-epidote-bearing Grey, migmatitic, tonalitic to granodioritic gneiss with Grey hornblende-epidote-biotite tonalitic orthogneiss Felsic Rocks Mineral Deposit Inventory Version 2 October 2002 Release; Ontario Geological Survey, Digital Data. Culshaw, N.G., Corrigan, D., Drage, J. and Wallace, P. 1988. Georgian Bay geological synthesis: Key Harbour to Dillon, Grenville Province of Ontario; in Current Research, Part C, Geological Survey of Canada, Paper 88-1C, p.129-133. Culshaw, N., Reynolds, P.H. and Check, G. 1991. A 40 39 Ar/ Ar study of post-tectonic cooling in the Britt domain of the Grenville Province, bA = biotite Ar/Ar date, in Ma Ontario; Earth and Planetary Science Letters, v.105, p.405-415. hA = hornblende Ar/Ar date, in Ma mA = muscovite Ar/Ar date, in Ma Heaman, L.M. and LeCheminant, A.N. 1993. Paragenesis and U-Pb wR = whole rock Rb/Sr date, in Ma systematics of baddeleyite (ZrO2); Chemical Geology, v.110, p.95-126. aU = allanite U/Pb date, in Ma dU = baddeleyite U/Pb date, in Ma Ketchum, J.W.F., Heaman, L.M., Krogh, T.E., Culshaw, N.G. and gU = garnet U/Pb date, in Ma Jamieson, R.A. 1998. Timing and thermal influence of late orogenic nU = monazite U/Pb date, in Ma extension in the lower crust: a U-Pb geochronological study from the tU = titanite U/Pb date, in Ma southwest Grenville orogen, Canada; Precambrian Research, v.89, zU = zircon U/Pb date, in Ma p.25-45. 50 50a Pink to grey leucocratic gneiss 18b Pink to grey, migmatitic leucogranite to granodiorite 53 55 55 CARLING TP Rainy 17a Unclassified granitoid orthogneiss 17b Monzonitic to granitic orthogneiss 56 Krogh, T.E. and Davis, G.L. 1970. Metamorphism 1700±100 m.y. and 900±100 m.y. ago in the northwest part of the Grenville Province in Mafic Rocks Mafic orthogneiss Krogh, T.E. and Davis, G.L. 1970. Isotopic ages along the Grenville Metasedimentary Rocks 15a p.309-313. Unclassified paragneiss 15b Marble; may be associated with rusty graphitic schist 15c Calc-silicate gneiss Krogh, T.E. and Davis, G.L. 1971. Paragneiss studies in the Georgian Bay area 90 km southeast of the Grenville Front; Carnegie Institution of Reynolds, P.H., Culshaw, N.G., Jamieson, R.A., Grant, S.L. and McKenzie, K. 1995. 40 39 Ar/ Ar traverse - Grenville Front Tectonic Zone to Britt Domain, Grenville Province, Ontario, Canada; Journal of Britt Domain (units 1 to 14) Metamorphic Geology, v.13, p.209-221. Grey biotite leucogneiss of granodioritic composition Tuccillo, M.E., Mezger, K., Essene, E.J. and van der Pluijm, B.A. 1992. Thermobarometry, geochronology and the interpretation of P-T-t data 14 Migmatitic Rocks in the Britt domain, Ontario Grenville orogen, Canada; Journal of Grey, migmatitic, leucocratic hornblende-biotite orthogneiss Petrology, v.33, p.1225-1259. of granodioritic to monzodioritic composition van Breemen, O., Davidson, A., Loveridge, W.D. and Sullivan, R.D. Migmatitic Rocks 1986. U-Pb zircon geochronology of Grenvillian tectonites, granulites Mafic Rocks Grey, leucocratic, migmatitic hornblende-biotite-garnet and igneous precursors, Parry Sound, Ontario; in The Grenville Amphibolite orthogneiss of tonalitic to granodioritic composition Province, Geological Association of Canada, Special Paper 31, p.191- 12 Metasedimentary Rocks 12a Unclassified paragneiss 12b Orthopyroxene-bearing, calcareous paragneiss, mafic 12c Mafic granulites gneiss and para-amphibolite Magnetic declination approximately 10°29'W in 2004. d 57 39 19b 58 15´ 59 45°30´00 560000m 61 62 563000m Geology not tied to surveyed lines. d Felsic Rocks Metric conversion factor: 11 1 foot = 0.3048 m. Metasedimentary Rocks CREDITS Intermediate to Felsic Granulites 10 Metasedimentary Rocks Rusty weathering, graphitic paragneiss N. Wodicka, 1987 to 1990. Intermediate to Felsic Granulites (layered) Grey, migmatitic, leucocratic garnet-biotite paragneiss, Unsubdivided, buff to grey weathering, layered, feldspathic locally with sillimanite; pink leucosome, may contain garnet, granulite muscovite, magnetite Intermediate to Felsic Granulites (retrogressed) Bayfield Gneiss Association (units 6 to 8) 36b Marble, calc-silicate tectonic breccia Digital drafting by S. Josey. Geology, legend and mineral deposit information reviewed by 8 Intermediate to Felsic Rocks Pink, sugary leucocratic gneiss Intermediate to Felsic Intrusive Rocks 7a Unsubdivided grey and pink, variably layered, highly strained orthogneiss, in places with recrystallized potassium feldspar megacrysts 6 Metasedimentary Rocks 6a Cartographic production by S. MacLean. To enable the rapid dissemination of information, this map has not received a technical edit. Discrepancies may occur for which the Ontario Ministry of Northern Development and Mines does not assume liability. Users should verify critical information. Grey, leucocratic, migmatitic hornblende-biotite-garnet orthogneiss of tonalitic to granodioritic composition Metasedimentary Rocks Layered paragneiss, garnet-rich granulite Geological compilation by N.G. Culshaw, 1991 and 2004. R.M. Easton. Mafic Rocks 36a Geology by N.G. Culshaw, D. Corrigan, J.W.F. Ketchum, P. Wallace and Metasedimentary Rocks Grey, leuco- to mesocratic garnet-biotite paragneiss, commonly with sillimanite; locally graphitic and Lake 50b 54 Krogh, T.E. and Davis, G.L. 1969. Geochronology of the Grenville Intermediate to Felsic Rocks 19b 16 Krogh, T.E. 1994. 1.45 Ga granulites in the southwestern Grenville Geology, v.22, p.215-218. 18a 7b 36 55 11 550000m age determination ABBREVIATIONS PARAUTOCHTHON NORTH OF PARRY SOUND DOMAIN 5040000m 559 75 38 49 bA 978 ± 6 Unsubdivided pink and grey leucocratic gneiss granulite or gneissic metagabbro 15 24 Nobel P.3550 Ontario Geological Survey 2002. Intermediate to Felsic Rocks Unsubdivided, layered, predominantly mafic two-pyroxene 42 50b GEORGIAN Novar Broadbent BASE OF LOWER GO HOME DOMAIN NOT OBSERVED 7 37 27 80 McKellar 69 Kearney Sprucedale Department of Mines, Geophysical Map 1507G, scale 1:63 360. (e.g., unit 39 or 40); pegmatite veins may be common Shawanaga 43 Dunchurch Front in Ontario; Carnegie Institution of Washington, Yearbook 68, 15 evidence of retrogression from a granulite facies precursor 18 50a 30 48 43b NATURE RESERVE 45 40 80 Pink, sugary, layered leucocratic gneiss (granodiorite, tonalite to diorite) orthogneiss containing 50a 53 54 (as classed by the Geological contact Unsubdivided, grey, foliated to gneissic, intermediate 15 19b tU 966 45 Wiwassasegen 85 10 50b 4 Lake 73 23 39 42 Raven 82 70 SHAWANAGA TP 75 72 70 nU 1062 ± 2 Magnetawan Burk's Falls Ardbeg Waubamik Dillon Pink, layered, leucocratic paragneiss zU 1050 dU 1152 ± 2 10 nU 1053 ± 2 25 Ahmic Harbour Ontario; Carnegie Institution of Washington, Yearbook 68, p.308-309. 9 gU 1435 ± 2 50a 43a 65 10 85 12 Intermediate to Felsic Rocks Unsubdivided, grey to buff weathering, orthopyroxene- 33 32 70 South River Sundridge Magnetawan Quartzite Buff to pink weathering, leucocratic granulite 40 25 14 70 23 14 23 85 10 60 75 64 19b 28 Port Loring North Province; Carnegie Institution of Washington, Yearbook 67, p.224-230. 43 80 80 9 gU 50a 1396 ± 6 75 41 Birch 50b 75 25 40 tU 1008 60 Island 30 10 44 55 65 50 20 41 32 52b 9 76 55 53 14 gf 60 20 65 discretionary Grey tonalitic orthogneiss Parry Sound Domain (interior) (units 36 to 41) I.R. 17 45 14 30 Pakesley Province: geologic setting, P-T conditions, and U-Pb geochronology; 18 61 9 62 21a 86 52b 9 SHAWANAGA 10 40 I.R. 17B 78 Interlayered amphibolite, semi-pelitic gneiss and PARRY SOUND DOMAIN (INTERIOR) 55 84 54 Key Commanda Ketchum, J.W.F., Jamieson, R.A., Heaman, L.M., Culshaw, N.G. and bearing intermediate (granodiorite, tonalite to diorite) 25 9 28 40 85 m-asymmetry 22a orthogneiss 35 NAISCOUTAING 19b 40 25 38 44c 44 Lake 78 10 46° Restoule 207. 80 40 14 33 30 33 Landing Amphibolite TECTONIC CONTACT WITH SUBJACENT 50a 80 9 Shawanaga 9 80 15 23 52b 45 15 85 50b 39 60 Shawanaga 64 tU 958 78 23 Intermediate Rocks Honey Harbour Gneiss Association (units 15 to 18) 13 51 83 60 65 27 12 55 70 80 20 78 45 17 55 10 55 55 70 Island 60 Island 55 45 40 50a 20 70 85 14 50a 40 10 11 37 34 18 30 Carolyn 11 70 9 45 84 50 15 31 65 Shawana ga River Lake 42 12 80 70 9 85 40 14 32 hA 964 ± 5 31 Island 65 80 45 10 11 33 35 65 Nadeau 50 Islands 5040000m 65 76 10 Black 11 14 52b 31 50 Sasega 87 20 40 45 81 bA 948 ± 5 35 35 65 Skerryvore 51 Oak Island 73 60 52b mA 904 ± 3 55 34 14 52 20 80 55 52b 25 45 35 42 30 30 8 65 15 Mafic orthogneiss 44b 70 49 30 30 11 16 24 35 60 35 53 11 30 44a Rock 11 24 70 75 32 75 prospects, 52 14 5 Black Lake 25 60 19 10 50 5 65 40 30 20 22 50 12 10 tU 1028 52b Mineral occurrences, Fold axis; minor fold, Nadeau Island Gneiss Association (units 9 to 14) 43 49 15 14 12 5 tU 1000 47 55 14 52b 85 26 45 50 12 Island 14 Channel 8 5 48 11 40 Grey, migmatitic layered gneiss quartzite 77 25 30 20 12 Pollard (with plunge) Pink, sugary, layered leucocratic gneiss gf 75 5 20 30 16 6 18 10 20 43 30 14 50 11 26 35 14 30 35 51 12 Island Jergens 50 30 26 48 r 25 10 24 30 Island 35 36 20 Rathlyn 26 14 40 20 O'Brien Islands 47 53 26 in opposite directions Pink, migmatitic, sugary leucocratic gneiss and subordinate Blackstone Lake Gneiss Association (units 42 and 43) 66 57 40 3 25 44 14 Shawana g a R iv e 20 40 Island 60 33 50 trend only, limbs dip z-asymmetry PARAUTOCHTHON SOUTH OF PARRY SOUND DOMAIN EAST BURPEE TP 63 10 65 Synform, interpreted; Fold axis; minor fold, ALLOCHTHON-PARAUTOCHTHON BOUNDARY Mafic and Metasedimentary Rocks 44d 25 5 Fossmill Pickerel Shallow Felsic Rocks (NADEAU ISLAND GNEISS ASSOCIATION): Intermediate to Felsic Rocks 46 56 30 8 Pentecost 15 75 30 20 50 50 20 10 35 14 30 14 17 40 80 17 85 43 Shawanaga Inlet 48 34 60 48 30 35 49 26 36 47 4 48 25 29 30 15 Island 40 35 20 45 Burnt 35 55 78 10 14 5 14 55 38 33 16 4 30 45 40 44 49 12b 10 67 70 15 49 40 80 25 Island 50 36 3 65 70 Island 68 42 45 14 37 33 50 30 25 20 16 33 82 35 75 45 12cb 72 Tonches 75 40 Kiosk 79° Powassan Washington, Yearbook 69, p.339-341. 44 14 17 70 15 17 14 40 in opposite directions unknown generation, TECTONIC CONTACT WITH SUBJACENT BRITT DOMAIN Granite Lake 24 58 10 31 85 32 Fold axis; minor fold, (with plunge) varied amounts of pink leucosome Grey, migmatitic tonalite to granodiorite orthogneiss 38 10 55 12 mA 896 ± 6 20 22 72 20 89 zU 1452 ± 2 70 tU 1024 36 45 50 Island 11 zU 1114 63 27 47 55 Barclay 40 20 46b 6 38 40 35 31 Lake 49 10 40 14 7b 18 tU 1005 57 44 30 trend only, limbs dip Grey, layered quartzofeldspathic gneiss containing 19b Felsic to Intermediate, Layered or Migmatitic Rocks 20 Tower 8 46 63 46 7b 65 49 20 65 27 75 60 75 25 5 7b 20 20 6a 50 40 22 70 46 46a 14 unknown generation, s-asymmetry Moon River Gneiss Association (units 44 to 46) 70 Lost Antiform, interpreted; subhorizontal) leucosome 16 Lake 14 Lineation (with plunge, Intermediate to Felsic Rocks Small outcrops of unit 47a or 47b hosted by adjacent 48 Turtle 85 14 19 Moon River Subdomain (units 42 to 46) 10 8 51 hanging-wall side fel............................................................feldspar 17 70 88 35 10 8 28 20 75 22 27 47 10 vertical) 35 tectonostratigraphic boundaries) (indicated by triangles) 35´ 12 20 52b trend only, teeth on ALLOCHTHON tU 1049 75 10 42 22 tU 1000 20 Weakly foliated to gneissic, mafic intrusive complex INTRUSIVE CONTACT tU 985 49 gf 20 60 Anorthosite, gabbroic anorthosite, minor gabbro 28 55 7b 80 80° Noëlville Rosseau Ojibway Gneiss Association (units 19 and 20) Small outcrops of unit 48a or 48b hosted by adjacent 49 Lake 20 20 30 45 40 45 thrust, interpreted; (trend only, inclined, Hornblende diorite, gabbro tU 961 17 26 20 21 3 644 60 60 65 80 Weakly foliated to gneissic metagabbro, primary Owl 30 75 55 8 Pointe au Baril Station 9 trend only unknown generation LATE PALEOPROTEROZOIC 49 24 8 tU 1004 29 40 6a 24 16 L g layering and/or Allochthon boundary intrusion (circa 1450 Ma) Lake 17 70 20 12 22 35´ tU 998 ± 15 n Lo 56 80 18 8 80 68 16 11 7b 70 28 70 17 6 26 d 37 n 39 8 7a 22 EARLY MESOPROTEROZOIC to Kibeong Lake 85 Alban Lower Go Home Domain (units 15 to 18) 63 34 22 5050000m 14 24 Fault, interpreted; foliation; 35 Unit 50a, with associated pink granite and grey country rock units (commonly found along Sucker Lake 20 Compositional Grey, migmatitic tonalitic and granodioritic orthogneiss Weakly foliated to gneissic, grey hornblende-biotite Argue la 30 25 16 48 45 47c Is 6a 11 Georgian Bay 7b 47b Lake 55 Niweme 82 35 grey, migmatitic leucogneiss consisting of gabbro, anorthosite and ultramafic rocks 49 25 7b 52 35 37 30 30 49 26 70 77 47a 55 16 11 69 81° Baril Station Mafic Intrusive Rocks, Anorthosite Suite 47 Spectacle 47 Bay d 6a 2 25 45 11 50 23 6b 51 Lake subsidiary agreement to the Economic and Regional Development P.3549 parallel tectonic 19c ek Cre 40 50 30 20 r ck e Su Lake Brewery 13 40 53 30 26 33 35 25 14 Unit 51a, with associated granite and monzonite Ontario 1985 Mineral Development Agreement (COMDA), a Inlet Intermediate to Felsic Rocks country rock units (indicated by dots) 23 25 77 4 8 18 5 85 52 30 48c 10 oo 19 50 45 7b 24 7a 23 igneous texture commonly preserved 48b Island 80 32 Lake Bird 70 Skunk 20 22 48 8 7b SYMBOLS 35 Intermediate Intrusive Rocks 48a r fish Rive Dog 7b 52 Bi g w 60 15 40 75 23 50 75 18 7b 84 60 6a 54 22 26 5050000m 6b 61 52 55 40 50 fel 8 Lake 10 19 41 25 18 78 36 60 25 the five-year Canada P.3548 Britt Felsic Rocks Mafic Intrusive Rocks 48 52 57 7b 70 23 70 20 50 25 23 24 35 33 50 45 Wilson Moose 57 Sturgeon 80 33 70 8 30 20 50 10 33 42 6a 53 7b 12 20 62 9 20 Bay Geological Synthesis, funded as part of Harbour Weakly foliated to gneissic, grey tonalite with associated 18 mapping program, Project C.2.3, Georgian Killarney Layered to podiform calc-silicate gneiss Weakly foliated to gneissic, pink monzonite, minor granodiorite and monzodiorite 78 27 65 15 Island 70 22 65 35 7a 60 51 80 49 70 6a 25 30 33 65 9 34 63 26 Gibraltar 30 42 23 8 6b 75 39 15 65 10 67 43 8 Harbour 5 30 27 24 72 67 Mapping was conducted as part of a three-year Trout Creek 35 granodiorite 8 Bayfield 17 53 Lake HARRISON TP 7b 3 58 29 52 Bayfield Inlet 40 50b Oxbow PROVINCIAL PARK Geological Survey. French River Metasedimentary Rocks Intermediate to Felsic Intrusive Rocks 50a STURGEON BAY 7b Cranberry Adjacent rocks may have been Mafic orthogneiss, amphibolite Shawanaga Domain (units 19 to 24) minor tonalite 35 65 26 Georgian 20 24 50 12 40 53 This map is published with the permission of the Director, Ontario Head Felsic to Intermediate Intrusive Rocks 54 57 7b 42 Unit 52a, strongly foliated to protomylonitic 51b Little Wilson e 6a 10 metamorphism at circa 1450 Ma. wholly overprinted by Grenvillian upper amphibolite facies metamorphism. syenite Lak NTS Reference: 41 H/9, 10 Agreement (ERDA) signed by the governments of Canada and Ontario. These rocks locally preserve evidence for granulite facies ALLOCHTHON-PARAUTOCHTHON BOUNDARY granodiorite, locally potassium feldspar megacrystic, 52 10 23 ile Lake 32 52c 41 70 35 86 522000m M 7b 16 Unit 52a, with associated granite and quartz monzonite, 51a Si x 65 10 57 55 Island 80°43´44 Lake 32 50 Mafic Rocks commonly potassium feldspar megacrystic Mile Six Pink, leucocratic granite, locally potassium feldspar 52b 55 51 7b Meneilly 53 13 Manbert 25 48a Passag e 7a Miskokway Horseshoe 8 7b Ale xand er 65 7b 55 d TECTONIC CONTACT WITH SUBJACENT LOWER GO HOME DOMAIN: megacrystic Evans Lake 48a 85 73 75 Grey, migmatitic tonalitic and granodioritic orthogneiss Felsic Intrusive Rocks 52a 85 8 85 52 64 80 7a 73 45 42 40 60 Island correspond to a suite or a complex. hornblende, biotite, epidote 85 7a 22 ann el Ch 35 54 46 33 7b If it were decided to 1983 North American Stratigraphic Code, in most cases, they would Grey, heterogeneous, leucosome-rich (>25%), Pink, sugary leucocratic granite gneiss COMMONLY CONTAINING GARNET 56 Lake 65 Big t DEFORMED AND MIGMATITIC ORTHOGNEISS, Lake 6a th 80 In le les fel 35 80 metamorphism or intrusion of mafic dikes. 29a "SINGLE CYCLE PLUTONIC ROCKS", VARIABLY 16 80 gneiss association is an informal stratigraphic term, introduced by Culshaw et al. (1988), that is primarily based on rock type, but which Sand Bay Gneiss Association (units 21 to 24) Lake 30 53 20 u 50 INTRUSIVE CONTACT 7b 42 66 65 26 Mafic Intrusive Rocks, Coronitic Metagabbro Suite (circa 1165 Ma) 2 km Pointe au Unit 54a, with associated anorthosite and gabbro pods Lone 87 48a 80 Ri v e r So 72 60 1 45° 48 8 map units in the legend may appear on the map face. A Pere Brebeuf Gneiss Association (units 25 and 26) Tree 80 80 27 coarse-grained, locally ophitic textured, metagabbro 57 81 8 22 28 Weakly foliated to gneissic mafic rocks of unknown Dark green to black, weakly foliated to gneissic, medium- to Lake 70 e dl id 77 75 Lake 48a 48 65 60 53 Seesee 34 15 Thus, not all Intermediate to Felsic Rocks 29b 25 74 7a Naiscoot C 65 49 el 54a 54b 40´ 44 Maps P.3548, P.3549, P.3550, P.3551 and P.3552. formally name a "gneiss association" as a lithodemic unit under the and slivers er 21 52a 78 67 68 0 Byng facies metamorphism and variably retrogressed 58 79 45 er Riv 7a 55 62 7b R iv laboratory investigations, including petrography and geochemistry. This is a legend common to Ontario Geological Survey Preliminary also may contain information with respect to plutonic history, protolith and of varied age, subjected to eclogite Gordon 7b 17 56 Grey biotite-muscovite-garnet-kyanite gneiss and schist c Mafic Rocks Naiscoot o ot 7b 78 58 t oo Nort h Cha nnel 30 83 30 is c Na 35 River 34 70 23 80 57 50 a is c 60 43 74 39 WITHIN THE GRENVILLE PROVINCE BURTON TP 7b 7b This legend is a field legend that locally incorporates the results of LOCATED WITHIN THE PARRY SOUND SHEAR ZONE Lake I.R. 17A 80 Nai scoot 35 80 50 45 51 3 7b 20 a Metasedimentary Rocks b HIGH-GRADE METAMORPHISM 59 60 70 48 54 12 85 75 50b Timber 17 1000 m 46° 80 7b NAISCOOT AREA © Lake 54 NAISCOUTAING 54 46 hA 974 ± 5 7b 42 16 7a 31 Island 50a mA 904 ± 6 57 83 70 30 60 6 56 45 40 30 29 MESOPROTEROZOIC 45 70 37 Straight and mylonitic gneiss derived from units 1a subjected to similar metamorphic conditions, but have been subsequently 8 75 Unit 1a, with minor amounts of unsubdivided polycyclic and/or 1b migmatitic granodioritic gneiss 85 58 7b (590 Ma) No leucosome older than the dikes is observed 1c MAP P.3549 Queen's Printer for Ontario, 2004. INTRUSIVE CONTACT 29 N 50b 55 48 Gneiss Association (unit 30) 5060000m Back 36 42 50b 45 20 32 77 4b 55 Wolf 70 85 58 metamorphosed mafic dikes (amphibolite). Mafic Intrusive Rocks (Grenville diabase dike swarm) r e iv migmatitic, granodiorite to tonalite containing 1b Ontario Geological Survey Scale 1:50 000 Mostly medium-grained, moderately foliated to gneissic, Para-amphibolite and unsubdivided paragneiss; includes Pine Island Gneiss Association (units 27 to 29) mA 899 ± 6 7b 8 80 60 36 20 Lake 44 80 80 5 50a 13 1a Mafic and Metasedimentary Rocks NEOPROTEROZOIC Littles 63 70 35 10 45 64 25 16 50b 25 50 16 55 65 55 7b 20 60 60 R Intermediate Migmatitic Rocks 1 Gneissic Rocks Structurally Below the Lighthouse Brown weathering, fine- to medium-grained diabase is r Mafic Rocks Upper Go Home Domain (units 25 to 29) Headquarters 30 38 30 4b Lake Lake 40 34 Quartzite, minor associated paragneiss grey to white sublithographic to lithographic limestone) 61 55 5 14 Pike Skunk 65 7b 50b 80 59 40´ 50b sillimanite gneiss; minor quartzite, calc-silicate gneiss and metasedimentary gneiss PRECAMBRIAN Lake Harris Lake 20 Layered, pink to grey quartz-feldspar-biotite paragneiss, locally with garnet-hornblende and garnet-kyanite and Amphibolite : PRECAMBRIAN GEOLOGY granodiorite orthogneiss TECTONIC CONTACT (SUSPECT) WITH THE SHAWANAGA DOMAIN, 7b Mafic monzodiorite gneiss Layered, migmatitic, grey tonalite, minor trondhjemite, grey to blue-grey interbedded limestone and dolostone, Grandpa 16 8 33a UNCONFORMITY Lake 50b 35 70 66 8 Mafic gneiss; minor metagabbro, anorthositic gneiss 3b Unsubdivided: includes Gull River Formation (light brown- Lake Log 3a Metasedimentary Rocks 2 Intermediate to Felsic Rocks with Metadiabase Dikes quartzofeldspathic gneiss and minor quartzite Chemical Sedimentary Rocks arkosic sandstone, pebbly sandstone, siltstone and shale) Sullivan Lake Long Moose Pike 20 44 8 48a Foster 15 10 p Lake 50 30 78 wR 1752 ± 95 75 20 45 63 38 ee 3 Quartzite, minor associated paragneiss and para-amphibolite and Shadow Lake Formation (calcareous red and green 62 Northern 35 40 70 5 25 48 56 Harris Lake 70 D ig B 35 53 54 30 45 Laird Rocks 10 5 7b 4b 36 70 35 25 15 4b 40 5 44 50a 10 6 7b 47 50 65 35 7b 36 32 15 30 10 10 36 50 18 65 4a 8 18 8 25 Norgate Inlet 60 Lake 24 20 48 68 30 50 11 50b 49 8 24 61 34 50b 45 85 60 70 75 50 66 56 16 8 1 50 34 75 47 66 65 Norgate 76 Giroux 65 zU 1457 ± 8 19 40 Mafic Rocks pelitic and garnet-rich gneiss interlayered with WALLBRIDGE TP 4a 38 31 Burton South Branch 66 35 38 6 82 84 2 2 10 57 4a 52a 5 60 5 20 3 10 50b 19 MIDDLE ORDOVICIAN 63 Lake 54 84 7b Doctor Magnetawan 4a 50b Mafic and Metasedimentary Rocks ORDOVICIAN South 5 85 46 57 50b 19 8 25 52a 11 47 20 35 50a 13 48 Predominantly grey gneiss with pink granitic leucosome Bustard Islands Gneiss Association (unit 1) 32 68 70 Pink, sugary leucocratic gneiss 4c 33b PALEOZOIC 43 74 63 4c 10 70 19 50 33 64 70 4b quartzite UNCONFORMITY 30 11 50b 36 and till 45 45 Unsubdivided pink and grey leucocratic gneiss Para-amphibolite, layered mafic gneiss, paragneiss and Glacial deposits; sand and gravel, clay 57 4a 50b 8 66 4a 4c 70 8 50b 4a Lighthouse Gneiss Association (units 31 to 33) 5 4a 4 Mafic Rocks PLEISTOCENE Lake 20 70 54 34 65 80 50b 1 11 Lake, stream and swamp deposits Granite 54 Intermediate to Felsic Rocks 35 RECENT Magnetawan 69 50 39 Tea Lake 5 4 Multicomponent layered gneiss and migmatite, minor Armer Bay Gneiss Association (units 34 and 35) QUATERNARY North MAGNETAWAN I.R. 1 27 30 BROWN TP Lake 4a 5 Parry Sound Domain (basal) (units 30 to 35) CENOZOIC 5066000m 8 8 50b Key Harbour Gneiss Association (units 2 to 5) LOCATED WITHIN PARRY SOUND SHEAR ZONE amphibolite Ri ve r 4a 50b 47 27 Island 529 18 65 an THRUST CONTACT WITH PARRY SOUND DOMAIN (BASAL), Intermediate to Mafic Migmatitic Rocks PHANEROZOIC Miner 17 4a eta w abc 45°45´00 Lake y 49 35 M agn 5 4 10 10 37 5 30 15 78 50b 54 53 52 51 61 560000m 59 LEGEND 80°10´58 a 28 44 50b 55 52b 550000m 49 48 47 46 MAGNETAWAN I.R. 1 4a 75 4a 45 44 58 57 56 B 50 22 4a Olga 50b 40 Island 45 50 50b 43 42 41 540000m 39 38 37 8 26 37 1 4a 36 35 34 33 ga Inl et 40 50a 70 32 34 52b 5066000m 31 530000m Sha wa na 45°45´00 29 28 a r 27 26 55 563000m 62 H 25 e 24 k 23 30´ 35´ 40´ 522000m 25´ a 80°43´40 15´ 20´ Issued 2004. Information from this publication may be quoted if credit is given. form: rusty weathering 6b Calc-silicate and amphibolite gneiss associated with garnet-biotite paragneiss of unit 6a Culshaw, N.G., Corrigan, D., Ketchum, J.W.F., Wallace, P. and Wodicka, N. 2004. Precambrian geology, Naiscoot area; Ontario Geological Survey, Preliminary Map P.3549, scale 1:50 000. 80°10´55 It is recommended that reference to this map be made in the following 81°00´00 501000m 02 03 04 06 05 50´ 55´ 07 510000m 09 08 12 11 13 16 15 14 19 18 17 40´ 45´ 22 21 520000m 24 23 530000m 29 28 27 26 25 Island STRUTHERS 70 51b Pi 51b Island l e re ck FRENCH RIVER I.R. 13 iv e re ek g C ke Da lle s iv Pickerel e r r e k 91 FRENCH RIVER I.R. 13 51b MIDDLE ORDOVICIAN Nisbet Lake 51b Lake 56 5 51b Lake French River 5090000m Island er Bucke Ri v nc h F re 89 Lake 47a 31 Mafic monzodiorite gneiss 2 Intermediate to Felsic Rocks with Metadiabase Dikes 33a Layered, pink to grey quartz-feldspar-biotite paragneiss, Layered, migmatitic, grey tonalite, minor trondhjemite, locally with garnet-hornblende and garnet-kyanite and granodiorite orthogneiss sillimanite gneiss; minor quartzite, calc-silicate gneiss Quartzite, minor associated paragneiss Mafic Rocks Amphibolite 1a Mostly medium-grained, moderately foliated to gneissic, migmatitic, granodiorite to tonalite containing Para-amphibolite and unsubdivided paragneiss; includes metamorphosed mafic dikes (amphibolite). pelitic and garnet-rich gneiss interlayered with leucosome older than the dikes is observed 1b grey to blue-grey interbedded limestone and dolostone, Gneissic Rocks Structurally Below the Lighthouse grey to white sublithographic to lithographic limestone) Gneiss Association (unit 30) 1c 89 Unit 1a, with minor amounts of unsubdivided polycyclic Straight and mylonitic gneiss derived from units 1a and/or 1b Metasedimentary Rocks This legend is a field legend that locally incorporates the results of Grey biotite-muscovite-garnet-kyanite gneiss and schist laboratory investigations, including petrography and geochemistry. b This is a legend common to Ontario Geological Survey Preliminary Maps P.3548, P.3549, P.3550, P.3551 and P.3552. LOCATED WITHIN THE PARRY SOUND SHEAR ZONE NEOPROTEROZOIC A gneiss association is an informal stratigraphic term, introduced by Culshaw et al. (1988), that is primarily based on rock type, but which also may contain information with respect to plutonic history, t Bass Lake 50 5 ox Cre e k 1a 4a 5 Brown weathering, fine- to medium-grained diabase iv e 45 hA 1020 ± 5 1a Gateway R l Grundy 1b 35 5 Dokis I sla n 40 30 30 Major 65 Island 30 44 52c 20 27 40 1a 52a 1b 40 51b 30 25 50a kA 980 ± 8 mA 934 ± 7 dU >1454 Outer Fox 46 50 Island 50b 52 51b 52 50 40 15 1a 45 45 2 51b 4a 4a 2 tU 972 ± 7 60 2 59 68 4a 50 4a 8 81 2 50b 50 2 2 5 2 Churchill 4 35 66 61 55 4a 6 20 6 80 40 4a 70 4a 50 27 47 2 4c 22 50 7 47 25 70 53 38 50a 4c 50a 50´ 4a 21 75 48 4c 4c 2 86 55 27 Ch 36 4a am p 25 50b la la Is d n 10 8 70 tU 990 ± 2 70 46 4a 50a 73 15 2 7 36 45 Rock 43 5 50b 58 10 20 14 65 15 43 75 25 9 13 50a 14 23 48a 72 10 35 21 44 5 70 20 32 20 11 40 17 15 30 ck Bla 70 ek Cre 35 75 3 4a 50 3 63 50 20 23 8 2 50b 37 2 17 2 53 50 4c 55 25 66 17 18 25 35 25 12 15 Bigwood 50a 50 15 69 Rocks 11 50 4a 5 02 03 04 05 06 07 55´ 08 09 510000m 11 12 13 50´ 14 15 16 17 18 19 45´ 520000m 21 22 23 24 25 26 40´ 27 30 68 530000m 31 19c Grey hornblende-epidote-biotite tonalitic orthogneiss 46 32 35´ 33 34 5067000m 4a 36 11 Orrville 35 Dorset Rosseau Port Sydney 141 BAY Tobermory Dwight 60 Huntsville Parry Sound 117 Sans Souci Dyer's Bay Baysville MacTier P.3551 118 400 Bala 118 Bracebridge 169 45° Edenhurst bA 978 ± 6 survey Location of isotopic age determination Honey Harbour 45° Purple Valley LAKE Penetanguishene Gravenhurst P.3552 Red Bay Norland Washago 12 Wiarton Nottawasaga 81° Midland Bay Leith Shallow 11 80° 169 79° Orillia 12 48 Brechin 26 Location Map 1 cm equals 25 km SOURCES OF INFORMATION Thematic information on this map is tied to a digital base map derived from map 41 H/15 of the National Topographic System, scale 1:50 000. Universal Transverse Mercator (UTM) co-ordinates are in North Intermediate to Felsic Rocks 43a Pink, sugary, layered leucocratic gneiss 43b Grey biotite leucogneiss of granodioritic composition Mafic Rocks Geological Survey of Canada Ontario Department of Mines 1965. Aeromagnetics, Key Harbour; Geological Survey of Canada Ontario ABBREVIATIONS Department of Mines, Geophysical Map 1508G, scale 1:63 360. Ontario Geological Survey 2002. Nb...........................................................niobium (MDI2) Mineral Deposit Inventory Version 2 October 2002 Release; Ontario Geological Survey, Digital Data. Corrigan, D., Culshaw, N.G. and Mortensen, J.K. 1994. Pre-Grenvillian evolution and Grenvillian overprinting of the Parautochthonous Belt in the Key Harbour area, Ontario: U-Pb constraints; Canadian Journal of Earth Sciences, v.31, p.583-596. Culshaw, N.G., Corrigan, D., Drage, J. and Wallace, P. 1988. Georgian Bay geological synthesis: Key Harbour to Dillon, Grenville Province of Ontario; in Current Research, Part C, Geological Survey of Canada, Paper 88-1C, p.129-133. bA = biotite Ar/Ar date, in Ma hA = hornblende Ar/Ar date, in Ma Culshaw, N., Reynolds, P.H. and Check, G. 1991. A 40 39 Ar/ Ar study of post-tectonic cooling in the Britt domain of the Grenville Province, Ontario; Earth and Planetary Science Letters, v.105, p.405-415. bK = biotite K/Ar date, in Ma kK = potassium feldspar K/Ar date, in Ma Cumming, G.L., Wilson, J.T., Farquhar, R.M. and Russell, R.D. 1955. mA = muscovite Ar/Ar date, in Ma Some dates and subdivisions of the Canadian Shield; Geological dU = baddeleyite U/Pb date, in Ma Association of Canada, Proceedings, v.7, p.27-79. nU = monazite U/Pb date, in Ma tU = titanite U/Pb date, in Ma Davidson, A. and Bethune, K.M. 1988. Geology on the north shore of zU = zircon U/Pb date, in Ma Georgian Bay, Grenville Province of Ontario; in Current Research, Part uW = uraninite Pb/Pb date, in Ma C, Geological Survey of Canada, Paper 88-1C, p.135-144. the Grenville Front, Ontario; in Radiogenic age and isotopic studies: Report 8; Geological Survey of Canada, Paper 94-F, p.107-114. 18b Pink to grey, migmatitic leucogranite to granodiorite Intermediate to Felsic Rocks metadiabase near Key Harbour, Britt domain, Grenville Province, 17a Unclassified granitoid orthogneiss Ontario; in Radiogenic age and isotopic studies 14, Geological Survey 17b Monzonitic to granitic orthogneiss of Canada, Current Research, Paper 2001-F7, 11p. (available in Mafic Rocks Mafic orthogneiss Metasedimentary Rocks 15a Lowdon, J.A. 1960. Age determinations by the Geological Survey of 60-17, 51p. Unclassified paragneiss 15b Marble; may be associated with rusty graphitic schist Lowdon, J.A. 1961. Age determinations by the Geological Survey of 15c Calc-silicate gneiss Canada, Report 2: isotopic ages; Geological Survey of Canada, Paper 61-17, 127p. Reynolds, P.H., Culshaw, N.G., Jamieson, R.A., Grant, S.L. and PARAUTOCHTHON NORTH OF PARRY SOUND DOMAIN McKenzie, K. 1995. 40 39 Ar/ Ar traverse - Grenville Front Tectonic Zone to Britt Domain, Grenville Province, Ontario, Canada; Journal of Britt Domain (units 1 to 14) 14 Migmatitic Rocks of granodioritic to monzodioritic composition 13 Metamorphic Geology, v.13, p.209-221. Magnetic declination approximately 10°22'W in 2004. Geology not tied to surveyed lines. Grey, migmatitic, leucocratic hornblende-biotite orthogneiss Metric conversion factor: 1 foot = 0.3048 m. Migmatitic Rocks CREDITS Grey, leucocratic, migmatitic hornblende-biotite-garnet orthogneiss of tonalitic to granodioritic composition 12 Metasedimentary Rocks N. Wodicka, 1987 to 1990. Unclassified paragneiss 11 Metasedimentary Rocks Pink, layered, leucocratic paragneiss Digital drafting by S. Josey. Metasedimentary Rocks Geology, legend and mineral deposit information reviewed by Felsic Rocks 10 Rusty weathering, graphitic paragneiss R.M. Easton. Intermediate to Felsic Granulites 9 Metasedimentary Rocks Cartographic production by S. MacLean. Grey, migmatitic, leucocratic garnet-biotite paragneiss, locally with sillimanite; pink leucosome, may contain garnet, To enable the rapid dissemination of information, this map has not muscovite, magnetite received a technical edit. Intermediate to Felsic Granulites (layered) Discrepancies may occur for which the Ontario Ministry of Northern Development and Mines does not assume Bayfield Gneiss Association (units 6 to 8) liability. Intermediate to Felsic Granulites (retrogressed) 8 Intermediate to Felsic Rocks Issued 2004. Users should verify critical information. Pink, sugary leucocratic gneiss Information from this publication may be quoted if credit is given. 7 recommended that reference to this map be made in the following 7a form: 538000m Unsubdivided grey and pink, variably layered, highly strained orthogneiss, in places with recrystallized 7b Mafic Rocks Metasedimentary Rocks 36a Layered paragneiss, garnet-rich granulite 36b Marble, calc-silicate tectonic breccia 80°30´00 It is Intermediate to Felsic Intrusive Rocks Grey, leucocratic, migmatitic hornblende-biotite-garnet orthogneiss of tonalitic to granodioritic composition 6 6a Grey, leuco- to mesocratic garnet-biotite paragneiss, commonly with sillimanite; locally graphitic and rusty weathering 6b Calc-silicate and amphibolite gneiss associated with garnet-biotite paragneiss of unit 6a 80 35 Nobel Pink to grey leucocratic gneiss Metasedimentary Rocks 36 37 GEORGIAN Novar Broadbent 18a Unsubdivided, layered, predominantly mafic two-pyroxene 36 75 8 37 49 36 50 Waubamik Dillon Kearney Sprucedale McKellar 69 Felsic Rocks granulite or gneissic metagabbro 40 66 50 5 29 Grey, migmatitic, tonalitic to granodioritic gneiss with potassium feldspar megacrysts 45°45´00 28 Grey metatextite with pink, hornblende-epidote-bearing 19b 529 40 42 45°45´00 501000m I.R. 1 38 4a denotes limits of area 19a Quartzite evidence of retrogression from a granulite facies precursor 56 4a 43 12 30 15 50a 85 645 WALLBRIDGE TP Inventory (MDI)) Limit of mapping; Zr...............................................................zircon (e.g., unit 39 or 40); pegmatite veins may be common MAGNETAWAN 56 50b Interlayered amphibolite, semi-pelitic gneiss and (granodiorite, tonalite to diorite) orthogneiss containing 50b 25 81°00´00 78 30 34 55 38 28 bA 1004 ± 6 44 Mineral Deposit U ............................................................uranium Unsubdivided, grey, foliated to gneissic, intermediate U hA 967 ± 7 30 60 40 McNab 60 35 Island 2 69 Byng Inlet 60 Burk's Falls Pointe au Baril Station granulite Magnetaw an Ri v er 65 30 Magnetawan Dunchurch BASE OF LOWER GO HOME DOMAIN NOT OBSERVED Unsubdivided, buff to grey weathering, layered, feldspathic 60 Island 5 39 5 4 55 70 50 Clark 4a 65 15 orthogneiss 64 fel 75 48 50 5 (as classed by the (interpreted) mapped during this Ahmic Harbour Ardbeg Canada, Report 1: isotopic ages; Geological Survey of Canada, Paper 48 85 73 32 30 5067000m 80 13 22 86 30 66 37 10 68 40 5 50a Byng electronic form only). 35 35 50 4a 17 Nb,gt,Th 5070000m Britt 45 66 44c bearing intermediate (granodiorite, tonalite to diorite) 11 mA 904 ± 8 Amphibolite Buff to pink weathering, leucocratic granulite 30 40 Mafic orthogneiss 44b Unsubdivided, grey to buff weathering, orthopyroxene- 60 17 10 10 41 67 25 65 50 69 71 57 South River Sundridge Magnetawan Geological compilation by N.G. Culshaw, 1991 and 2004. Britt 36 P.3548 Geology by N.G. Culshaw, D. Corrigan, J.W.F. Ketchum, P. Wallace and 84 16 50a 44a TECTONIC CONTACT WITH SUBJACENT 20 65 4a occurrences Geological contact Migmatitic Rocks uW 875 Station 65 Port Loring North Davidson, A. and van Breemen, O. 2001. Baddeleyite U-Pb age of Mafic and Metasedimentary Rocks Parry Sound Domain (interior) (units 36 to 41) 5 Pakesley Britt Davidson, A. and van Breemen, O. 1994. U-Pb ages of granites near 18 Amphibolite 72 Key Commanda Honey Harbour Gneiss Association (units 15 to 18) Intermediate to Felsic Rocks uW 1043 fel 35 75 50a kK 835 ± 50 50 4c 4c Grey, migmatitic layered gneiss PARRY SOUND DOMAIN (INTERIOR) 15 32 27 U 42 37 20 14 47 bK 779 ± 50 St gn 23 4c 54 discretionary Th............................................................thorium 5 80 50a 62 75 20 46b 34 80 45 50 5 50b 5070000m 43 Zr,U,fel REE,Nb 45 8 29 54 fel, 65 28 49 65 15 12 60 20 75 25 39 6 35 20 6 25 55 54 75 10 71 17 prospects, (with plunge) Unsubdivided pink and grey leucocratic gneiss PARAUTOCHTHON SOUTH OF PARRY SOUND DOMAIN 73 Be,Th,Ti, 22 5 16 50 70 Still River 38 4a m-asymmetry St gn ..............................................stone, gneiss Blackstone Lake Gneiss Association (units 42 and 43) 21 3 10 25 86 53 48 Mineral occurrences, Intermediate to Felsic Rocks Nadeau Island Gneiss Association (units 9 to 14) 60 4 17 9 Pink, sugary, layered leucocratic gneiss quartzite 39 4c 46a 44d 31 38 10 4 50b fel 66 4c 40 fel 31 35 Fold axis; minor fold, fel ...........................................................feldspar (NADEAU ISLAND GNEISS ASSOCIATION): 38 16 in opposite directions Quartzite ALLOCHTHON-PARAUTOCHTHON BOUNDARY Felsic to Intermediate, Layered or Migmatitic Rocks 52 31 36 3 85 72 Flat Rock 46 45 4a 35 65 45 42 25 56 4a 26 63 49 HENVEY TP 51 2 Bessener 24 45 9 24 38 44 74 24 4c 26 34 15 60 13 50 63 (with plunge) kA = potassium feldspar Ar/Ar date, in Ma Grey, migmatitic tonalite to granodiorite orthogneiss 48 50 25 45 80 50a trend only, limbs dip 21e TECTONIC CONTACT WITH SUBJACENT BRITT DOMAIN 40 30 15 45 26 64 5 80 10 43 52 50a 15 50 38 55 45 34 35 50 11 27 26 2 47 2 8 in 74 6 18 25 60 34 38 75 65 50 Intersection lineation Be.........................................................beryllium varied amounts of pink leucosome 16 46 Still River 35 55 25 47 4a 51 35 leucosome 35 53 unknown generation, Para-amphibolite Moon River Gneiss Association (units 44 to 46) 50´ 41 4c 50 19 Moon River Subdomain (units 42 to 46) 36 5 2 50b 4a 21 7 Synform, interpreted; Ti ............................................................titanium 17 53 78 22 50a 20 43 50b 17 INTRUSIVE CONTACT 48 32 42 subhorizontal) Calc-silicate gneiss LATE PALEOPROTEROZOIC 76 83 46° Restoule Head REE .....................................rare earth elements EARLY MESOPROTEROZOIC to 77 Fossmill Lion's Lineation (with plunge, 21d ALLOCHTHON 50a 27 56 4 5 23 34 in opposite directions 35 Kiosk 79° Powassan Pickerel 6 gt .............................................................garnet 24 16 trend only, limbs dip 21c Lower Go Home Domain (units 15 to 18) 20 50 60 17 47 15 40 34 52 22 unknown generation, Pink to grey marble Small outcrops of unit 47a or 47b hosted by adjacent 17 10 Foliation (inclined) 21b tectonostratigraphic boundaries) (indicated by triangles) 18 22 42 Georgian Bay 5 HENVEY INLET I.R. 2 5 Antiform, interpreted; Medium to dark grey, biotite-rich quartz-plagioclase Ojibway Gneiss Association (units 19 and 20) Weakly foliated to gneissic, mafic intrusive complex 27 52 50 4c Anorthosite, gabbroic anorthosite, minor gabbro country rock units (commonly found along 50b 5 21a horizons consisting of gabbro, anorthosite and ultramafic rocks 47c 28 32 30 8 10 46 4a bA 993 ± 5 76 33 63 35 4b Small outcrops of unit 48a or 48b hosted by adjacent 78 52 39 2 21 10 84 29 Islands mA 922 ± 3 46 56 2 Islands 37 18 30 39 Weakly foliated to gneissic metagabbro, primary 48c 47a 80° Noëlville P.3550 paragneiss and schist ("Dillon schist") with quartzite Unit 50a, with associated pink granite and grey Hornblende diorite, gabbro 60 5 only vertical) Metasedimentary Rocks Mafic Intrusive Rocks, Anorthosite Suite Bekanon 4c 53 20 Dark grey dioritic orthogneiss, possible hypabyssal Weakly foliated to gneissic, grey hornblende-biotite 48b 47b 28 30 Henvey 2 58 38 77 4a 75 21 71 24 16 39 79 11 13 50a 36 3 5 4a 35 11 Alban American Datum 1983 (NAD83), Zone 17. Unit 51a, with associated granite and monzonite igneous texture commonly preserved 47 51 22b intrusion (circa 1450 Ma) Intermediate Intrusive Rocks 48a 5 36 Grey tonalitic orthogneiss Mafic Intrusive Rocks 48 20 40 30 40 22a country rock units (indicated by dots) 38 37 45 5 2 26 55 46 Intermediate Rocks Weakly foliated to gneissic, pink monzonite, minor granodiorite and monzodiorite 38 65 5 2 51b 45 55 46 70 57 51 5 50b 70 27 54 65 18 50a 2 22 15 50a 48 3a 8 Pink, migmatitic, sugary leucocratic gneiss and subordinate Weakly foliated to gneissic, grey tonalite with associated 34 51b 22 er 49 70 48a 4a 78 70 Unit 52a, strongly foliated to protomylonitic granodiorite iv 5080000m 5 50 76 R 5 2 4a 4a e y 12 51b zU 1442 ± 7 50a 12 5 57 Felsic Rocks grey, migmatitic leucogneiss Unit 52a, with associated granite and quartz monzonite, minor tonalite K 58 50b 23 granodiorite, locally potassium feldspar megacrystic, 50b zU 945 ± 47 12 79 22 hA 968 ± 5 50a 55 37 4b 27 47a 5 45 78 Grey, layered quartzofeldspathic gneiss containing Intermediate to Felsic Intrusive Rocks 81 26 bA 978 ± 6 30 51b 50a 27 40 50 50 Lake 40 (trend only, inclined, Intermediate to Felsic Rocks Straight 40 10 50a mA 924 ± 3 4a 45 5080000m 10 kA 902 ± 6 45 26 60 Pink, leucocratic granite, locally potassium feldspar 2 51b 62 51b 50 80 26 St gn 81 12 58 21 18 46 13 40 5 50a Gull Rocks 1a Island zU 1146 ± 137 47 54 interpreted; trend syenite e tl 50 subsidiary agreement to the Economic and Regional Development HURON 24 Felsic to Intermediate Intrusive Rocks 51a 82 20 21 40 55 53 65 48 52c Ludgate 51 52 54 8 3b Mann 25 zU 1684 ± 8 1a 47 Key River Key River Lineament, unknown generation Grey, migmatitic tonalitic and granodioritic orthogneiss commonly potassium feldspar megacrystic it L 50 50a Bigsby 1a Ontario 1985 Mineral Development Agreement (COMDA), a P.3549 foliation; Shawanaga Domain (units 19 to 24) megacrystic 32 25 15 44 70 mA 903 ± 9 Key Harbour 50b Island 52 66 20 1a 55 4a tU ~980 Island 50 1b 51b 51b 52a 83 r 5 40 75 zU 1456 ± 12 Dead 45 60 4b tU 1015 ± 16 30 35 the five-year Canada Inlet Felsic Intrusive Rocks 52b 52a 4a 51b Bay Geological Synthesis, funded as part of Trout Creek trend only parallel tectonic Pink, sugary leucocratic granite gneiss hornblende, biotite, epidote Key Ri v e nU 1035 ± 1 Islands 1b mapping program, Project C.2.3, Georgian 46° Fault, interpreted; layering and/or Felsic Rocks ALLOCHTHON-PARAUTOCHTHON BOUNDARY Portage Lake 51b 5 Bustard Tanvat Mapping was conducted as part of a three-year Harbour Compositional 35 COMMONLY CONTAINING GARNET 50a 60 50 4a 1bc 47a 45 1c 81 DEFORMED AND MIGMATITIC ORTHOGNEISS, 50a 45 Geological Survey. Killarney Layered to podiform calc-silicate gneiss "SINGLE CYCLE PLUTONIC ROCKS", VARIABLY n Cree k 45 84 4a Metasedimentary Rocks Sand Bay Gneiss Association (units 21 to 24) 51b 4a 37 Burnt INTRUSIVE CONTACT 51b 52 Island 82 30 Mafic orthogneiss, amphibolite TECTONIC CONTACT WITH SUBJACENT LOWER GO HOME DOMAIN: coarse-grained, locally ophitic textured, metagabbro Cranberry 1a hA 990 ± 5 (circa 1165 Ma) 9 35 Islands 83 Pakesley 50a 35 1a 1c 50a 75 1a hA 998 ± 8 53 522 25 zU 1013 ± 2 kA 922 ± 8 Mafic Intrusive Rocks, Coronitic Metagabbro Suite 55´ 30 REE 48 This map is published with the permission of the Director, Ontario French River Intermediate to Felsic Rocks 25 Dark green to black, weakly foliated to gneissic, medium- to 30 26 Unit 54a, with associated anorthosite and gabbro pods 69 45 50 hA 991 ± 5 9 nd Isla ick dd Pu 38 40 NTS Reference: 41 H/15 81° Mafic Rocks Pere Brebeuf Gneiss Association (units 25 and 26) Weakly foliated to gneissic mafic rocks of unknown and slivers MOWAT TP 85 mA 932 ± 7 52c 54a 54b Gut Lake 20 4a 51b 50 80 51b 4a 5 47a ds ar bo 5 4a Beka no T in F 54 protolith and of varied age, subjected to eclogite 35 1a Island 2 km Agreement (ERDA) signed by the governments of Canada and Ontario. Grey, migmatitic tonalitic and granodioritic orthogneiss 35 facies metamorphism and variably retrogressed kA 936 ± 8 hA 992 ± 8 84 Dock 27 er 86 Island 38 correspond to a suite or a complex. Grey, heterogeneous, leucosome-rich (>25%), SYMBOLS Mafic Rocks d mA 931 ± 7 45 e h WITHIN THE GRENVILLE PROVINCE 50a 1bc 35 r ge Ri v 50a 1a 55´ g Fox 45 85 ka Lake 50 28 HIGH-GRADE METAMORPHISM s e 35 52b zU 1467 ± 11 h Lake 50 Clear 50 1983 North American Stratigraphic Code, in most cases, they would 29a P a Gurd Lake 50a 25 MESOPROTEROZOIC k 50a 20 86 1 69 1a 1c Intermediate to Felsic Rocks 29b INTRUSIVE CONTACT 87 Islands 30 29 PARK P ic 87 51b 25 If it were decided to migmatitic granodioritic gneiss PROVINCIAL 70 k e re 52b kA 917 ± 8 51b (590 Ma) GRUNDY LAKE r 1b 45 52c 55 metamorphism or intrusion of mafic dikes. formally name a "gneiss association" as a lithodemic unit under the Mafic Intrusive Rocks (Grenville diabase dike swarm) 88 51b F 1a 51b ek re 88 Pine Island Gneiss Association (units 27 to 29) C 47a 1c Thus, not all map units in the legend may appear on the map face. c Upper Go Home Domain (units 25 to 29) e hA 1005 ± 8 a TECTONIC CONTACT (SUSPECT) WITH THE SHAWANAGA DOMAIN, is b 0 Queen's Printer for Ontario, 2004. 30 PRECAMBRIAN N No 1000 m © Lake kA 929 KEY HARBOUR AREA Scale 1:50 000 Intermediate Migmatitic Rocks 1 Mafic and Metasedimentary Rocks UNCONFORMITY King's Island Ontario Geological Survey PRECAMBRIAN GEOLOGY and metasedimentary gneiss 51b Pakeshkag Mafic gneiss; minor metagabbro, anorthositic gneiss 3b Unsubdivided: includes Gull River Formation (light brown- 50a 50 PROVINCIAL PARK 3a Metasedimentary Rocks quartzofeldspathic gneiss and minor quartzite Chemical Sedimentary Rocks arkosic sandstone, pebbly sandstone, siltstone and shale) 5 Quartzite, minor associated paragneiss and para-amphibolite and Shadow Lake Formation (calcareous red and green 1bc FRENCH RIVER Mafic Rocks 3 ORDOVICIAN Fox Rock Mafic and Metasedimentary Rocks Bustard Islands Gneiss Association (unit 1) 32 Lake 5090000m Predominantly grey gneiss with pink granitic leucosome 33b PALEOZOIC Tower 4c UNCONFORMITY R 47a Lake River quartzite a R k nc h 33 h Fr e s ke r a and till Junction 51b Walter French Pink, sugary leucocratic gneiss Glacial deposits; sand and gravel, clay 57 92 P Suc 91 55 39 re Unsubdivided pink and grey leucocratic gneiss 4b Lighthouse Gneiss Association (units 31 to 33) 50a Key 34 5 50 C 4a Para-amphibolite, layered mafic gneiss, paragneiss and PLEISTOCENE 26 Pike Lake Intermediate to Felsic Rocks 4 Mafic Rocks : MAP P.3548 Lake, stream and swamp deposits 92 35 RECENT Cantin Lake 5 Multicomponent layered gneiss and migmatite, minor Armer Bay Gneiss Association (units 34 and 35) QUATERNARY 47a 5 Intermediate to Mafic Migmatitic Rocks 5 Parry Sound Domain (basal) (units 30 to 35) CENOZOIC Cantin Island er Riv 5093000m 51b 5 Pickerel Riv er TRAVERS TP Key Harbour Gneiss Association (units 2 to 5) LOCATED WITHIN PARRY SOUND SHEAR ZONE amphibolite Merranger's 5093000m THRUST CONTACT WITH PARRY SOUND DOMAIN (BASAL), Island Wanikewin 60 47a abc PHANEROZOIC 94 Mile Fourteen Mile Island 1bc 51b 538000m 37 36 Fourteen McDougal 94 King's Island 35 34 33 46°00´00 46°00´00 TP LEGEND 80°30´00 35´ 32 31 Culshaw, N.G., Corrigan, D., Ketchum, J.W.F., Wallace, P. and Wodicka, N. 2004. Precambrian geology, Key Harbour area; Ontario Geological Survey, Preliminary Map P.3548, scale 1:50 000.