The record has been much deformed, reconstituted, and obliterated during the subsequent Proterozoic and Phanerozoic eons. |
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Scattered throughout the Pena Negra migmatites there are small bodies of Upper Proterozoic gneissic granodiorite and granite. |
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Archaean and Proterozoic basement terranes are commonly dissected by swarms of Precambrian mafic dykes. |
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Precambrian divisions such as the Proterozoic and the Archean were conventionally eras but are now often referred to as eons. |
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Subsequently, between the Late Proterozoic and the Mesozoic, the rocks throughout the region suffered periodic episodes of deformation. |
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This is the general name for all Archaean and Proterozoic basement gneisses of the NW Scotland mainland and Outer Hebrides. |
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Archean and most Proterozoic sedimentary rocks are notable for their distinct lack of any bioturbated textures. |
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The Indian plate rocks include late Archaean, Proterozoic and Phanerozoic continental margin sequences. |
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Recent studies of Proterozoic orogenic belts have shown that they may be underlain, at mid to lower crustal levels, by keels of Archaean crust. |
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The key to understanding the early evolution of eukaryotes lies in the Proterozoic fossil record, especially microfossils. |
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Major crustal rifting has also played a part in the evolution of large bodies of Proterozoic sedimentary and igneous rocks. |
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This session will focus on the evolution of magmatic and lithospheric processes during the Proterozoic. |
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Several are associated with monocyclic Proterozoic basins, like those of Mont-Laurier and Wakeham. |
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Stratigraphically he has studied both Lower and Middle Proterozoic strata and Lower Paleozoic strata. |
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Scattered throughout the Mojave Desert, outcrops of Proterozoic sedimentary rock make up parts of the mountain ranges that divide this region into basins. |
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Mafic enclaves in basement gneisses indicate oceanic to island arc conditions during the latest Archaean to earliest Proterozoic period. |
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Acritarchs continue to be used in studies of Proterozoic paleoecology and stratigraphy, even though their systematic affinities are still not well understood. |
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Proterozoic oceans on Earth held much more oxygen at the surface than their oxygen deserts at depth. |
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Although his stratigraphic studies have focused primarily on the Proterozoic and Cambrian, he has also worked on Triassic and Jurassic strata. |
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By the beginning of the Proterozoic 2.5 billion years ago, the Earth would have begun to look more familiar to us. |
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The Proterozoic aeon saw episodic increases in atmospheric oxygen content. |
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The zircon data clearly lead to the conclusion that a Proterozoic terrane is the main detritus source because of the preponderance of grains from this age. |
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The area is underlain by rocks of the Abitibi Subprovince intruded by Proterozoic diabase dykes with a number of different trends and ages. |
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It consists of uplifted Proterozoic sedimentary rocks intruded by Late Proterozoic diabase dykes and sills. |
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The rocks are Archean in Age, except for a series of diabase dykes from the Proterozoic Period. |
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The Archaean to Proterozoic Lewisian complex, exposed along and in the Moine Thrust Zone, represents the last stages of the growth and reworking of the Hebridean craton. |
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Proterozoic dolomite, if fractured within strands and tensional bulges of the wrench systems, are also potential gas reservoirs. |
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Mineralized bodies formed by hydrothermal replacement of a Middle Proterozoic dolomite within an intraplate rift environment. |
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The basement of the Ordos Basin is Archaeozoic and lower Proterozoic metamorphic rocks. |
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The Ordos Basin is located in the southwest of the North China platform on an Archaeozoic and early Proterozoic granite and metamorphic basement. |
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His main areas of interest are Proterozoic tectonic evolution, U-Pb geochronology and secular changes in geological processes. |
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His current focus of research is on Proterozoic evolution of the lithosphere and links to orogenic gold, magmatic nickel and diamond exploration. |
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The bulk of the Mozambique belt of eastern Africa and Madacascar is underlain by deeply eroded and multiply deformed high-grade Proterozoic and Archaean rocks. |
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In Proterozoic carbonaceous fossils, ultrastructural and biochemical characters are unavailable, and anatomical and reproductive structures are uncommon. |
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The apparent increase of carbonaceous macrofossils through the Proterozoic Eon is likely a result of combined biological and environmental evolution. |
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Aspects of both the Archean and Proterozoic geology, including the role of heat producing elements, are explored to try and understand the extensive crustal deformation. |
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Proterozoic mafic and ultramafic intrusions within the Hearne also have geological and geochemical characteristics of contaminated and sulphidic magmas. |
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The Paleozoic comes after the Neoproterozoic era of the Proterozoic and is followed by the Mesozoic. |
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This granite was intruded into the Late Proterozoic to Cambrian metasediments of the Dalradian Supergroup. |
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The Paleozoic comes after the Neoproterozoic Era of the Proterozoic Eon and is followed by the Mesozoic Era. |
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Geochemical evidence strongly indicates that the total mass of plankton has been similar to modern levels since early in the Proterozoic. |
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The is especially likely for earlier periods such as the Paleozoic and Proterozoic. |
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Applications of isotope geochemistry, most specifically U-Pb geochronology, to studies of continental lithospheric evolution, with particular emphasis on Archean to Proterozoic processes. |
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Todd Project is situated within the southeastern portion of the Early Proterozoic Pine Creek Geosyncline. |
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Tony's research has primarily been on Proterozoic volcanism, plutonism, and tectonics in Nunavut, and has involved field mapping and geochemical techniques, including regional isotopic surveys. |
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He has been responsible mainly for stratigraphic and geochronological research on many of the Proterozoic sedimentary sequences that occur within this region. |
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He is currently leading the preparation of chapters on Proterozoic stratigraphy for an upcoming GSC stratigraphic atlas for northern mainland Canada. |
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The Hadean, Archean and Proterozoic eons were as a whole formerly called the Precambrian. |
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Sometimes the Hadean, Archean and Proterozoic are lumped together in a supereon called the Precambrian. |
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All growth models predict that the formation of the continental crust was essentially completed by late Archean to Early Proterozoic, and the amount of new crust produced in the Phanerozoic is minor or insignificant. |
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Stromatolites and fenestral fabric in Early Proterozoic Huronian Supergroup, Ontario. |
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Exploration is focused on Noril'sk type sulphide Cu-Ni-PGE-Au targets associated with Proterozoic ultramafic intrusions. |
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The Western Churchill is an extensive Archean and Proterozoic tract of land that contains a number of large magmatic terranes conducive to hosting Ni-Cu-PGE mineralization. |
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Archean metavolcanic and metasedimentary rocks are unconformably overlain by Proterozoic rocks of the Huronian Supergroup. |
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The Kalia I deposit is found within the axial region of the Lower Proterozoic greenstone belt. |
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However, macroscopic fossils are now known from the late Proterozoic. |
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The Mundrabilla Fault is readily interpretable as a sinistral transpressional fault formed during Proterozoic north-west directed Australia-wide compression. |
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At the Thompson Mine and Birchtree Mine, a series of early Proterozoic rocks belonging to the Ospwagan Group are interfolded with Archean gneisses of indeterminate origin. |
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Target 1 is a body of lower Proterozoic anorthosite with features suggestive of the presence of a platinum reef that has been traced on the surface for four miles. |
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West African has a landholding of 6,370sq km and 200km of strike length of early Proterozoic Birimian greenstone belts, which are highly prospective for gold mineralisation. |
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