Characterization and petrologic interpretation of olivine‐rich basalts
... Received 29 April 2005; revised 15 July 2005; accepted 26 July 2005; published 6 January 2006. ...
... Received 29 April 2005; revised 15 July 2005; accepted 26 July 2005; published 6 January 2006. ...
AGGREGATES
... C 128) is defined as the ratio of its mass to the mass of an equal volume of water. It is used in certain computations for mixture proportioning and control. Most natural aggregates have relative densities between 2.4 and 2.9 (2400 and 2900 kg/ m3). ...
... C 128) is defined as the ratio of its mass to the mass of an equal volume of water. It is used in certain computations for mixture proportioning and control. Most natural aggregates have relative densities between 2.4 and 2.9 (2400 and 2900 kg/ m3). ...
MANTLE- AND CRUST-DERIVED MAGMATISM IN THE
... lower εNd(t) compared with the TIB. The sources of the mafic magmatism can be interpreted in terms of a depleted mantle, variously overprinted by fluids and melts from subducted slabs. In the west (TIB), H2O-dominated fluids percolated and prepared shallower (lower Ce/Yb; spinel lherzolite field) ma ...
... lower εNd(t) compared with the TIB. The sources of the mafic magmatism can be interpreted in terms of a depleted mantle, variously overprinted by fluids and melts from subducted slabs. In the west (TIB), H2O-dominated fluids percolated and prepared shallower (lower Ce/Yb; spinel lherzolite field) ma ...
Timing and Tectonic Setting of Volcanogenic
... histories. A consequence of this is that the extensional settings that host VMS deposits occur repeatedly over time and space within the CMB. Not all extensional events have VMS mineralization associated with them (Fig. 2). In some circumstances the absence of VMS can be related to regional environm ...
... histories. A consequence of this is that the extensional settings that host VMS deposits occur repeatedly over time and space within the CMB. Not all extensional events have VMS mineralization associated with them (Fig. 2). In some circumstances the absence of VMS can be related to regional environm ...
Station 1 Identify Specimen 1a Identify Specimen 1b Identify
... surfaces due to weakness in the atomic structure. 2. _____________is the ability of a mineral to withstand scratching 3. _____________ is when a mineral breaks unrelated to weaknesses ...
... surfaces due to weakness in the atomic structure. 2. _____________is the ability of a mineral to withstand scratching 3. _____________ is when a mineral breaks unrelated to weaknesses ...
Soils, geomorphology, landscape evolution, and land
... The object of this field trip is to examine the geology, landforms, soils, and land use in the eastern Blue Ridge and western Piedmont geologic provinces in Orange County in central Virginia. A complex mix of igneous, sedimentary, and metamorphic bedrocks, ranging in age from Mesoproterozoic to Tria ...
... The object of this field trip is to examine the geology, landforms, soils, and land use in the eastern Blue Ridge and western Piedmont geologic provinces in Orange County in central Virginia. A complex mix of igneous, sedimentary, and metamorphic bedrocks, ranging in age from Mesoproterozoic to Tria ...
An Overview of the Carlton Rhyolite Group: Cambrian A
... 2 and 533 ± 4 Ma, respectively (Hames et al., 1998). These results overlap zircon ages for the Wichita granites and are consistent with field evidence that some of the Roosevelt gabbros were emplaced at about the same time as the granites (Price et al., 1998a; Gilbert and Hogan, 2010). However, the ...
... 2 and 533 ± 4 Ma, respectively (Hames et al., 1998). These results overlap zircon ages for the Wichita granites and are consistent with field evidence that some of the Roosevelt gabbros were emplaced at about the same time as the granites (Price et al., 1998a; Gilbert and Hogan, 2010). However, the ...
Open-File Report 2005-1235
... Table 1. Description of the spatial databases prepared for the Northern Rocky Mountains compilation....... 6 Table 2. List and description of digital files developed for this report........................................................... 7 Table 3. Summary of the ArcInfo® feature attribute table ...
... Table 1. Description of the spatial databases prepared for the Northern Rocky Mountains compilation....... 6 Table 2. List and description of digital files developed for this report........................................................... 7 Table 3. Summary of the ArcInfo® feature attribute table ...
Geologic Map of the Prisor Hill Quadrangle, Sierra
... Ar40/Ar39 age of 33.6 Ma. was determined by McIntosh et al (1991). The tuff is a pale pinkish-orange to grayish-red crystal ash-flow tuff, somewhat less welded compared to tuff 5, and contains fewer and smaller crystals. Broken sanidine, quartz, biotite, and plagioclase crystals are set in a matrix ...
... Ar40/Ar39 age of 33.6 Ma. was determined by McIntosh et al (1991). The tuff is a pale pinkish-orange to grayish-red crystal ash-flow tuff, somewhat less welded compared to tuff 5, and contains fewer and smaller crystals. Broken sanidine, quartz, biotite, and plagioclase crystals are set in a matrix ...
Nitrogen concentration and d N of altered oceanic crust obtained on
... et al., 1984; Boyd et al., 1992; Cartigny et al., 2003). Between the time from their eruption at MOR to their subduction into trenches, oceanic basalts potentially undergo extensive water–rock interaction with seawater over a wide range of temperatures (Alt et al., 1986), perhaps even involving biog ...
... et al., 1984; Boyd et al., 1992; Cartigny et al., 2003). Between the time from their eruption at MOR to their subduction into trenches, oceanic basalts potentially undergo extensive water–rock interaction with seawater over a wide range of temperatures (Alt et al., 1986), perhaps even involving biog ...
geology and mineral resources in the ojo caliente no. 2 mining
... well-cemented, massive to thin-bedded, volcaniclastic conglomerate, sandstone, and siltstone; includes a white ash-fall or ash-flow tuff north of Black Mountain andesite flows interbedded with volcaniclastic sedimentary rocks (Tc) gray, welded to nonwelded tuff containing 5-30% phenocrysts (quartz, ...
... well-cemented, massive to thin-bedded, volcaniclastic conglomerate, sandstone, and siltstone; includes a white ash-fall or ash-flow tuff north of Black Mountain andesite flows interbedded with volcaniclastic sedimentary rocks (Tc) gray, welded to nonwelded tuff containing 5-30% phenocrysts (quartz, ...
profiles
... natural history encyclopaedia. c AD 1000 Al-Beruni (973–1050) observes that different grades of sediment is deposited by different strengths of river currents—an early observation of sedimentology. He also puts precious minerals into geological context. ...
... natural history encyclopaedia. c AD 1000 Al-Beruni (973–1050) observes that different grades of sediment is deposited by different strengths of river currents—an early observation of sedimentology. He also puts precious minerals into geological context. ...
Volcanogenic Massive Sulfide Deposits
... VMS deposits are among the oldest ore deposits on Earth, with examples in the Pilbara of Western Australia and the Barberton and Murchison greenstone belts of South Africa that date back to 3.45 billion years (Huston et al., 2010a). As a result, the fossil record of seafloor hydrothermal activity is ...
... VMS deposits are among the oldest ore deposits on Earth, with examples in the Pilbara of Western Australia and the Barberton and Murchison greenstone belts of South Africa that date back to 3.45 billion years (Huston et al., 2010a). As a result, the fossil record of seafloor hydrothermal activity is ...
Arc magmas sourced from mélange diapirs in subduction zones
... zones at the slab-mantle interface. The trace-element pattern of average mélange rocks is similar to those of subduction-related volcanic rocks, with their distinctive relative enrichment in Pb and their depletion in Nb, Ta and Ti (Fig. 1b). Enrichment and depletion in Pb and Nb are best expressed r ...
... zones at the slab-mantle interface. The trace-element pattern of average mélange rocks is similar to those of subduction-related volcanic rocks, with their distinctive relative enrichment in Pb and their depletion in Nb, Ta and Ti (Fig. 1b). Enrichment and depletion in Pb and Nb are best expressed r ...
abo quadrangle, western half - New Mexico Bureau of Geology
... Stream alluvium (late Holocene to late Pleistocene) – poorly sorted, sandy to gravelly alluvium along valley bottoms; includes deposits underlying low stream terraces along some of the major drainages. Most Qa sediments are reddish in color, except in some of the terraces along Cañon Latigo and near ...
... Stream alluvium (late Holocene to late Pleistocene) – poorly sorted, sandy to gravelly alluvium along valley bottoms; includes deposits underlying low stream terraces along some of the major drainages. Most Qa sediments are reddish in color, except in some of the terraces along Cañon Latigo and near ...
the physical and historical framework
... uplifted area, covering the region with lava and ash. The largest volcanic event was the explosive eruption of the Amalia Tuff from the Questa caldera about 25 million years ago, approximately coincident with the onset of the next great event, Rio Grande rifting. The Bear Canyon pluton, visible in R ...
... uplifted area, covering the region with lava and ash. The largest volcanic event was the explosive eruption of the Amalia Tuff from the Questa caldera about 25 million years ago, approximately coincident with the onset of the next great event, Rio Grande rifting. The Bear Canyon pluton, visible in R ...
The Elements of Geology W. H. Norton
... added to those already in the field. The present work, however, is the outcome of the need of a text−book of very simple outline, in which causes and their consequences should be knit together as closely as possible,a need long felt by the author in his teaching, and perhaps by other teachers also. ...
... added to those already in the field. The present work, however, is the outcome of the need of a text−book of very simple outline, in which causes and their consequences should be knit together as closely as possible,a need long felt by the author in his teaching, and perhaps by other teachers also. ...
40. Evolution of a layered diorite-gabbro to become a layered quartz
... (Fig. 6) and increase in size (Fig. 7) until at the top of the hill, the layered rocks look similar to those found along Route 69 (e.g., Fig. 3). These microcline patches in the feldspathic layers are not single microcline crystals but aggregates of smaller microcline crystals, the same size as adja ...
... (Fig. 6) and increase in size (Fig. 7) until at the top of the hill, the layered rocks look similar to those found along Route 69 (e.g., Fig. 3). These microcline patches in the feldspathic layers are not single microcline crystals but aggregates of smaller microcline crystals, the same size as adja ...
Provenance characteristics of the Brumunddal sandstone in the Oslo
... calated with up to 30m thick, volcanoclastic conglomerates and sandstones. The conglomerates consist entirely of rhomb porphyry lava clasts while the sandstones contain63-65% quartz, 30-32 % feldspar (mostly plagioclase) and 4-6% lava fragments and hence classify as an arkosic arenite. The volcanoc ...
... calated with up to 30m thick, volcanoclastic conglomerates and sandstones. The conglomerates consist entirely of rhomb porphyry lava clasts while the sandstones contain63-65% quartz, 30-32 % feldspar (mostly plagioclase) and 4-6% lava fragments and hence classify as an arkosic arenite. The volcanoc ...
The Realm of Ultrahigh- Pressure Metamorphism
... with pressures above the quartz-to-coesite transition are pressure polymorph of SiO2 , was independently discovultrahigh-pressure metamorphic rocks by defi nition (e.g. ered in two different crustal rocks almost 30 years ago. Chopin 2003; Liou et al. 2009; FIG. 4). Coesite and diamond Christian Chop ...
... with pressures above the quartz-to-coesite transition are pressure polymorph of SiO2 , was independently discovultrahigh-pressure metamorphic rocks by defi nition (e.g. ered in two different crustal rocks almost 30 years ago. Chopin 2003; Liou et al. 2009; FIG. 4). Coesite and diamond Christian Chop ...
The western margin of Mexico is ideally - Earth Science
... The main feature that characterizes the Guerrero composite terrane and separates it from neighboring terranes is its large volumes of volcanic and volcaniclastic rocks that range in age from Middle Jurassic to Late Cretaceous, deposited in mainly submarine environments. In previous publications, the ...
... The main feature that characterizes the Guerrero composite terrane and separates it from neighboring terranes is its large volumes of volcanic and volcaniclastic rocks that range in age from Middle Jurassic to Late Cretaceous, deposited in mainly submarine environments. In previous publications, the ...
Geology - Alagappa University
... Fundamental concepts – significance of structure, process and time – A brief account on concepts of Davis and Penck on the evolution of landforms – Characteristic features of landforms – Characteristics and types of fluvial landforms – Fluvial cycle – concept of peneplains – stream rejuvenation, cau ...
... Fundamental concepts – significance of structure, process and time – A brief account on concepts of Davis and Penck on the evolution of landforms – Characteristic features of landforms – Characteristics and types of fluvial landforms – Fluvial cycle – concept of peneplains – stream rejuvenation, cau ...
Marsco and Mheall a` Mhaoil
... granites of the British Tertiary Volcanic Province from other, deeper-level granites such as those of Caledonian age in Scotland. The granites are characteristically found as stocks and ring-dykes emplaced into brittle crust and their chemical compositions indicate equilibration at low-pressures, eq ...
... granites of the British Tertiary Volcanic Province from other, deeper-level granites such as those of Caledonian age in Scotland. The granites are characteristically found as stocks and ring-dykes emplaced into brittle crust and their chemical compositions indicate equilibration at low-pressures, eq ...
Economic geology research, volume 1 1999-2000
... Granberg, Viterliden, Gråberget, Sarvasåive, Sadenåive, Vaikijaur, Iekelvare, and Sjisjka. Most deposits share common characteristics, such as being hosted by intermediate to felsic intrusive rocks. They are all also Cu±Au±Fe oxide dominated deposits with a similar ore mineralogy and they generally ...
... Granberg, Viterliden, Gråberget, Sarvasåive, Sadenåive, Vaikijaur, Iekelvare, and Sjisjka. Most deposits share common characteristics, such as being hosted by intermediate to felsic intrusive rocks. They are all also Cu±Au±Fe oxide dominated deposits with a similar ore mineralogy and they generally ...
Origin of Chert in Mississippian Monte Cristo Formation, Southern
... arencaeous limestone (Bray, 1983). The Dawn ranges in thickness from about 15 m at Crystal Pass south of Goodsprings to over 50 m thick at Sloan. The Dawn is considered to be equivalent to the Whitmore Wash Member of the Redwall Limestone in the Grand Canyon area of Arizona and the Tin Mountain Lime ...
... arencaeous limestone (Bray, 1983). The Dawn ranges in thickness from about 15 m at Crystal Pass south of Goodsprings to over 50 m thick at Sloan. The Dawn is considered to be equivalent to the Whitmore Wash Member of the Redwall Limestone in the Grand Canyon area of Arizona and the Tin Mountain Lime ...
Clastic rock
Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus, chunks and smaller grains of rock broken off other rocks by physical weathering. Geologists use the term clastic with reference to sedimentary rocks as well as to particles in sediment transport whether in suspension or as bed load, and in sediment deposits.