Formation and Evolution of Granite Magmas During
... scattered diffuse neosome patches (Fig. 2b) in which the S1 foliation disappears and the grainsize has increased. This process only affected the leucocratic members of the grey gneiss that contain quartz, plagioclase and Kfeldspar; hence, the term palaeosome applies only to these fertile bulk compos ...
... scattered diffuse neosome patches (Fig. 2b) in which the S1 foliation disappears and the grainsize has increased. This process only affected the leucocratic members of the grey gneiss that contain quartz, plagioclase and Kfeldspar; hence, the term palaeosome applies only to these fertile bulk compos ...
1.8 Billion Years of Detrital Zircon Recycling Calibrates a
... Geochronological studies of highly resistant detrital zircon grains are reshaping our view of how sediment moves through sedimentary basins and across continents in response to global tectonics [12]. The phenomenon of recycling is an established part of the sedimentary cycle, nonetheless, detrital z ...
... Geochronological studies of highly resistant detrital zircon grains are reshaping our view of how sediment moves through sedimentary basins and across continents in response to global tectonics [12]. The phenomenon of recycling is an established part of the sedimentary cycle, nonetheless, detrital z ...
Article
... Geochronological studies of highly resistant detrital zircon grains are reshaping our view of how sediment moves through sedimentary basins and across continents in response to global tectonics [12]. The phenomenon of recycling is an established part of the sedimentary cycle, nonetheless, detrital z ...
... Geochronological studies of highly resistant detrital zircon grains are reshaping our view of how sediment moves through sedimentary basins and across continents in response to global tectonics [12]. The phenomenon of recycling is an established part of the sedimentary cycle, nonetheless, detrital z ...
Getting to Know Vesta PSRD: Getting to Know Vesta
... depth, made mostly of magnesium-rich, calcium-poor orthopyroxene. Eucrites have basaltic compositions with ironrich pyroxene and sodium-poor plagioclase and may have formed from surface or near-surface lavas or as cumulates. Scientists think some basaltic eucrites were later metamorphosed by heat. T ...
... depth, made mostly of magnesium-rich, calcium-poor orthopyroxene. Eucrites have basaltic compositions with ironrich pyroxene and sodium-poor plagioclase and may have formed from surface or near-surface lavas or as cumulates. Scientists think some basaltic eucrites were later metamorphosed by heat. T ...
Igneous Environments
... 6. Magma that reaches the surface erupts as lava (molten rock that flows on the surface) or as volcanic ash. Volcanic ash forms when dissolved gases in the magma expand and blow the magma apart into small fragments of volcanic glass. Any igneous rock that forms on the surface is called an extrusive r ...
... 6. Magma that reaches the surface erupts as lava (molten rock that flows on the surface) or as volcanic ash. Volcanic ash forms when dissolved gases in the magma expand and blow the magma apart into small fragments of volcanic glass. Any igneous rock that forms on the surface is called an extrusive r ...
On the relationship between the Bushveld Complex and its felsic
... grains (400–600 µm). The texture, as noted, is classic granoblastic (Fig. 4). The rock also contains sparse plagioclase porphyroblasts up to 2 mm long. These display normal zoning near the margins, which encase abundant quartz grains. No other porphyroblasts are present. Typical modes are estimated ...
... grains (400–600 µm). The texture, as noted, is classic granoblastic (Fig. 4). The rock also contains sparse plagioclase porphyroblasts up to 2 mm long. These display normal zoning near the margins, which encase abundant quartz grains. No other porphyroblasts are present. Typical modes are estimated ...
SEABED CHARACTER MAPPING IN THE GREAT AUSTRALIAN
... newly defined terrains. The rocks of the eastern Arunta region have also undergone multiple deformation and metamorphic events that are now being unravelled. This complex history will also be illustrated during the excursion. The second aspect that will be illustrated in this field trip is the metal ...
... newly defined terrains. The rocks of the eastern Arunta region have also undergone multiple deformation and metamorphic events that are now being unravelled. This complex history will also be illustrated during the excursion. The second aspect that will be illustrated in this field trip is the metal ...
Geochemical and Geochronological Investigations in the
... crystallization age. Rb-Sr whole-rock isochron ages from separate localities are 1490+/-20 Ma and 1497+/-42 Ma. Sphene/whole-rock/biotite isochron ages and initial 87Sr/86Sr ratios from separate localities are indistinguishable from those of whole-rock isochrons. In both cases feldspar plots above t ...
... crystallization age. Rb-Sr whole-rock isochron ages from separate localities are 1490+/-20 Ma and 1497+/-42 Ma. Sphene/whole-rock/biotite isochron ages and initial 87Sr/86Sr ratios from separate localities are indistinguishable from those of whole-rock isochrons. In both cases feldspar plots above t ...
976 Frenchman Map Units
... development and >1-m-thick gypsic horizons with stage V salt development. Carbonate rinds on some clasts exceed 2 cm in thickness and are commonly micritic in character. The deposits are poorly stratified and consist of pebble to boulder gravels that are poorly to moderately sorted and poorly to mod ...
... development and >1-m-thick gypsic horizons with stage V salt development. Carbonate rinds on some clasts exceed 2 cm in thickness and are commonly micritic in character. The deposits are poorly stratified and consist of pebble to boulder gravels that are poorly to moderately sorted and poorly to mod ...
Fluorite Ridge Mines
... Fluorite Ridge is composed of a stock of monzonite porphyry (Tertiary) intruded into older rocks that cap the eminences and occur as disconnected masses on the sides of the ridge. These older rocks consist of Paleozoic sedimentaries resting on a basement of pre-Cambrian granite and overlain by Lower ...
... Fluorite Ridge is composed of a stock of monzonite porphyry (Tertiary) intruded into older rocks that cap the eminences and occur as disconnected masses on the sides of the ridge. These older rocks consist of Paleozoic sedimentaries resting on a basement of pre-Cambrian granite and overlain by Lower ...
ore deposit types and their primary expressions
... near the surface, biological processes can also concentrate and transport ore components or remove non-ore components. Hydrothermal fluids are a major transport medium for many ore systems; these fluids are essentially water, with lesser and variable amounts of CO2, H2S, SO2, CH4, N2, NaCl and other s ...
... near the surface, biological processes can also concentrate and transport ore components or remove non-ore components. Hydrothermal fluids are a major transport medium for many ore systems; these fluids are essentially water, with lesser and variable amounts of CO2, H2S, SO2, CH4, N2, NaCl and other s ...
Petrogenesis of High Heat Producing Granite
... Fereyid and South Eastern Desert areas with the Arabo-Nubian Shield belt (Adb El-Naby and Saleh, 2003; Abbady et al., 2006). They normally have high uranium (up to 30 ppm) and low Th (up to 23 ppm) contents (Adb ElNaby and Saleh, 2003; Abbady et al., 2006). Neoproterozoic HHP granites in South Afric ...
... Fereyid and South Eastern Desert areas with the Arabo-Nubian Shield belt (Adb El-Naby and Saleh, 2003; Abbady et al., 2006). They normally have high uranium (up to 30 ppm) and low Th (up to 23 ppm) contents (Adb ElNaby and Saleh, 2003; Abbady et al., 2006). Neoproterozoic HHP granites in South Afric ...
Robinson-7873.pm - Mineralogical Society of America
... depth (Patrick and Miller 1997; cf. Wiebe 1993; Anderson and Smith 1995). This cross-sectional exposure provides an unusual view of open-system magma chamber processes. The Aztec Wash pluton can be divided into two distinct, major zones (Figs. 1 and 2): a lower heterogeneous zone (H zone) and an upp ...
... depth (Patrick and Miller 1997; cf. Wiebe 1993; Anderson and Smith 1995). This cross-sectional exposure provides an unusual view of open-system magma chamber processes. The Aztec Wash pluton can be divided into two distinct, major zones (Figs. 1 and 2): a lower heterogeneous zone (H zone) and an upp ...
Advances in Ni-Cu-PGE Sulphide Deposit Models and Implications
... and maximize value from empirical geoscience observations that form the basis for project selection and then targeting of exploration using advanced geochemical and geophysical technologies. The petrologic characteristics of the host rocks can effectively be used to rank exploration approaches in pr ...
... and maximize value from empirical geoscience observations that form the basis for project selection and then targeting of exploration using advanced geochemical and geophysical technologies. The petrologic characteristics of the host rocks can effectively be used to rank exploration approaches in pr ...
Crustal contamination of mafic magmas: evidence from a
... (Mohr, 1987). The crust is both a density filter and a source of incompatible elements (Lightfoot et al., 1991) and it may act as a site of extensive and extensive partial crystallization of primitive melts (O’Hara and Herzberg, 2002). However, there is much debate whether the trace element and isot ...
... (Mohr, 1987). The crust is both a density filter and a source of incompatible elements (Lightfoot et al., 1991) and it may act as a site of extensive and extensive partial crystallization of primitive melts (O’Hara and Herzberg, 2002). However, there is much debate whether the trace element and isot ...
Evolution of the Eocene Galisteo Basin, north
... (Dickinson, 1970). The lack of substantial volcanic lithic fragments (except in the uppermost Galisteo) suggests very little or no contribution from volcanic sources. The presence of well rounded quartz, rounded overgrowths of quartz and some chert fragments indicates contributions from sedimentary ...
... (Dickinson, 1970). The lack of substantial volcanic lithic fragments (except in the uppermost Galisteo) suggests very little or no contribution from volcanic sources. The presence of well rounded quartz, rounded overgrowths of quartz and some chert fragments indicates contributions from sedimentary ...
The generation of high Sr/Y plutons following Late Jurassic arc–arc
... constraints from detrital zircon populations in deformed sedimentary rocks and 206Pb/238U zircon ages of post-kinematic fault-stitching plutons bracket contractional deformation between ~159 and 154 Ma (Schwartz et al., 2011). The widespread ~N–S-directed contractional features in the BMP have been ...
... constraints from detrital zircon populations in deformed sedimentary rocks and 206Pb/238U zircon ages of post-kinematic fault-stitching plutons bracket contractional deformation between ~159 and 154 Ma (Schwartz et al., 2011). The widespread ~N–S-directed contractional features in the BMP have been ...
Chapter 21: Metamorphism
... The IUGS-SCMR proposed this definition: “Metamorphism is a subsolidus process leading to changes in mineralogy and/or texture (for example grain size) and often in chemical composition in a rock. These changes are due to physical and/or chemical conditions that differ from those normally occurring a ...
... The IUGS-SCMR proposed this definition: “Metamorphism is a subsolidus process leading to changes in mineralogy and/or texture (for example grain size) and often in chemical composition in a rock. These changes are due to physical and/or chemical conditions that differ from those normally occurring a ...
M40-49-8-7-eng - Publications du gouvernement du Canada
... has special metallogenetic importance, as they are the source rocks for more than 75% of the metals mined i n the world (Gross, 1993a). Iron deposits include the common iron-rich oxide, silicate, carbonate, and sulphide lithofacies of iron-formation which are described in the following papers. Other ...
... has special metallogenetic importance, as they are the source rocks for more than 75% of the metals mined i n the world (Gross, 1993a). Iron deposits include the common iron-rich oxide, silicate, carbonate, and sulphide lithofacies of iron-formation which are described in the following papers. Other ...
THE GEOLOGY AND GEOCHEMISTRY OF BERYLLIUM IN
... interest in beryllium and beryllium alloys. These technological ad vances have brought about accelerated exploration programs by numer ous organizations searching for beryllium. In order to assist in the general exploration for beryllium, a survey was conducted of all known beryllium deposits in s ...
... interest in beryllium and beryllium alloys. These technological ad vances have brought about accelerated exploration programs by numer ous organizations searching for beryllium. In order to assist in the general exploration for beryllium, a survey was conducted of all known beryllium deposits in s ...
Relation between Coal and Fly Ash Mineralogy, Based on
... the ash for adsorbed trace elements, which may be loosely held to the glass surfaces and thus have significant potential for release into the surrounding environment. Glass in natural volcanic rocks is relatively unstable during chemical weathering, and glass in coal ash may also be expected to brea ...
... the ash for adsorbed trace elements, which may be loosely held to the glass surfaces and thus have significant potential for release into the surrounding environment. Glass in natural volcanic rocks is relatively unstable during chemical weathering, and glass in coal ash may also be expected to brea ...
Earth Science - First Semester Exam Review Sheet
... EX: Define Atom: The smallest part of an element that still has or retains the properties of that element. This is not all you should know, what else? An atom is made of protons which are positively charged found in the nucleus, neutrons which are neutral and found in the nucleus, electrons which ar ...
... EX: Define Atom: The smallest part of an element that still has or retains the properties of that element. This is not all you should know, what else? An atom is made of protons which are positively charged found in the nucleus, neutrons which are neutral and found in the nucleus, electrons which ar ...
Bulletin 26: Geology of the Gran Quivira Quadrangle, New Mexico
... surface consists of alternating ridges and valleys. This condi tion is especially characteristic of the area west and southwest of Abo. Closer to the Chupadera Mesa escarpment the strata have in places been dissected into small erosion remnants held up by resistant beds; examples are the prominent b ...
... surface consists of alternating ridges and valleys. This condi tion is especially characteristic of the area west and southwest of Abo. Closer to the Chupadera Mesa escarpment the strata have in places been dissected into small erosion remnants held up by resistant beds; examples are the prominent b ...
Geologic Map of the Idaho Part of the Grangeville 30 x 60 Minute
... use a normative feldspar classification scheme (Barker, 1979) to distinguish tonalite and trondhjemite. PreMiocene volcanic rocks are classified by total alkalies versus silica chemical composition according to IUGS recommendations (Le Maitre, 1984). The Miocene Columbia River Basalt Group contains ...
... use a normative feldspar classification scheme (Barker, 1979) to distinguish tonalite and trondhjemite. PreMiocene volcanic rocks are classified by total alkalies versus silica chemical composition according to IUGS recommendations (Le Maitre, 1984). The Miocene Columbia River Basalt Group contains ...
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.