Tectonic setting of Late Cretaceous gold and mercury
... plutons and subaerial mafic to felsic volcanic rocks; their chemistry indicates a mantle component. The structurally controlled dikes, sills, and stocks are felsic to intermediate and commonly peraluminous in composition. They are the same age as the volcanicplutonic complexes, but their geochemical ...
... plutons and subaerial mafic to felsic volcanic rocks; their chemistry indicates a mantle component. The structurally controlled dikes, sills, and stocks are felsic to intermediate and commonly peraluminous in composition. They are the same age as the volcanicplutonic complexes, but their geochemical ...
the granulite belt of lapland and the belomorides
... the eastern Baltic Shield is characterized by two adjacent high-grade belts (Tana and Granulite belts) located between the Archean Inari-Kola craton to the east and the South Lapland-Karelia craton to the west. The Tana belt corresponded to a volcanic sequence (tholeiitic and calcalkaline series) su ...
... the eastern Baltic Shield is characterized by two adjacent high-grade belts (Tana and Granulite belts) located between the Archean Inari-Kola craton to the east and the South Lapland-Karelia craton to the west. The Tana belt corresponded to a volcanic sequence (tholeiitic and calcalkaline series) su ...
1:500K Tectonic units of Western Australia
... 1000 Tectonic and magmatic events affecting the tectonic unit (ages in brackets indicate maximum and minimum age in millions of years) ...
... 1000 Tectonic and magmatic events affecting the tectonic unit (ages in brackets indicate maximum and minimum age in millions of years) ...
"Bedrock Geology of New York City: More than 600 m.y. of geologic
... miles along strike. Yonkers has a concordant, stratiform character, and therefore must be a metavolcanic (not plutonic) body. Zircons from the Yonkers gneiss in Westchester County have been dated at 563 Ma (Rankin and others, 1997), compatible with Late Neoproterozoic rifting elsewhere. Bimodal (maf ...
... miles along strike. Yonkers has a concordant, stratiform character, and therefore must be a metavolcanic (not plutonic) body. Zircons from the Yonkers gneiss in Westchester County have been dated at 563 Ma (Rankin and others, 1997), compatible with Late Neoproterozoic rifting elsewhere. Bimodal (maf ...
Recycling lower continental crust in the North China craton
... Foundering of mafic lower continental crust into underlying convecting mantle has been proposed as one means to explain the unusually evolved chemical composition of Earth’s continental crust1,2, yet direct evidence of this process has been scarce. Here we report that Late Jurassic high-magnesium an ...
... Foundering of mafic lower continental crust into underlying convecting mantle has been proposed as one means to explain the unusually evolved chemical composition of Earth’s continental crust1,2, yet direct evidence of this process has been scarce. Here we report that Late Jurassic high-magnesium an ...
modern accretionary processes The Palaeoproterozoic Trans
... profound changes in continental plate configuration and tectonic processes (e.g. Griffin et al. 2008; Hou et al. 2008), ocean and atmospheric compositions (e.g. Anbar & Knoll 2002) and the biosphere (e.g. Konhauser et al. 2002). By 2.5 Ga, Archaean cratons had grown by tectonic and magmatic accretio ...
... profound changes in continental plate configuration and tectonic processes (e.g. Griffin et al. 2008; Hou et al. 2008), ocean and atmospheric compositions (e.g. Anbar & Knoll 2002) and the biosphere (e.g. Konhauser et al. 2002). By 2.5 Ga, Archaean cratons had grown by tectonic and magmatic accretio ...
The Pecos greenstone belt - New Mexico Geological Society
... broadly similar to suites found in some Archean greenstone belts such as those in the western Vermilion District, northeastern Minnesota (Morey, 1978) and South Surgeon Lake, Ontario (Franklin, 1978). The most abundant rock type within the volcanic suite is fine- to medium-grained amphibolite, or me ...
... broadly similar to suites found in some Archean greenstone belts such as those in the western Vermilion District, northeastern Minnesota (Morey, 1978) and South Surgeon Lake, Ontario (Franklin, 1978). The most abundant rock type within the volcanic suite is fine- to medium-grained amphibolite, or me ...
Evolution of the East African and related orogens, and the assembly
... that occurred between 530 and 515 Ma in the form of E-verging thrusting. Collins and his co-workers suggest that the boundary between the Itremo Group and underlying Archean–Proterozoic gneisses (their Antanarivo Block) is an extensional structure named the Betsileo shear zone. They also suggest tha ...
... that occurred between 530 and 515 Ma in the form of E-verging thrusting. Collins and his co-workers suggest that the boundary between the Itremo Group and underlying Archean–Proterozoic gneisses (their Antanarivo Block) is an extensional structure named the Betsileo shear zone. They also suggest tha ...
Chapter 4. TTG & Genesis of the Continental Crust
... TTG is an acronym for “tonalite-trondhjemite-granodiorite”. These granitoids, together with greenstone belts, are a typical feature of all Archean terrains. In addition, a rarer feature of Archean terrains is the occurrence of high-Mg diorite-tonalite-granodiorite rocks, collectively called “sanuki ...
... TTG is an acronym for “tonalite-trondhjemite-granodiorite”. These granitoids, together with greenstone belts, are a typical feature of all Archean terrains. In addition, a rarer feature of Archean terrains is the occurrence of high-Mg diorite-tonalite-granodiorite rocks, collectively called “sanuki ...
EPITHERMAL Au
... CAPSULE DESCRIPTION: Quartz veins, stockworks and breccias carrying gold, silver, electrum, argentite and pyrite with lesser and variable amounts of sphalerite, chalcopyrite, galena, rare tetrahedrite and sulphosalt minerals form in high- level (epizonal) to near-surface environments. The ore common ...
... CAPSULE DESCRIPTION: Quartz veins, stockworks and breccias carrying gold, silver, electrum, argentite and pyrite with lesser and variable amounts of sphalerite, chalcopyrite, galena, rare tetrahedrite and sulphosalt minerals form in high- level (epizonal) to near-surface environments. The ore common ...
Plateau uplift in western Canada caused by lithospheric
... thrust belt into the foothills belt16 . Previous studies in the interior of the Cordillera have documented a regionally flat Moho12 and hot upper mantle5,14 . West of the RMT, our tomographic model shows that an upper-mantle layer, with sufficiently low velocity to be asthenosphere, extends from the ...
... thrust belt into the foothills belt16 . Previous studies in the interior of the Cordillera have documented a regionally flat Moho12 and hot upper mantle5,14 . West of the RMT, our tomographic model shows that an upper-mantle layer, with sufficiently low velocity to be asthenosphere, extends from the ...
tectonic models for the geological evolution of crust, cratons and
... Abstract The earliest sialic crust was probably destroyed by meteorite impacts, leaving only detrital 4.2-3.9 Ga zircons in later sediments. The oldest rocks are 3.9-3.8 Ga high-grade gneisses commonly associated with lavas and sediments which were transported into the deep crust. They indicate that ...
... Abstract The earliest sialic crust was probably destroyed by meteorite impacts, leaving only detrital 4.2-3.9 Ga zircons in later sediments. The oldest rocks are 3.9-3.8 Ga high-grade gneisses commonly associated with lavas and sediments which were transported into the deep crust. They indicate that ...
Thermochronology of the Trans
... Figure 1 - Map showing main subdivisions and structural elements ofthe Trans-Hudson Orogen in northern Saskatchewan and Manitoba. Ensialic blocks are patterned; largely juvenile arc-related terranes are not. C-SBZ, Churchill-Superior Boundary Zone; HB, Hanson Lake Block; TZ, Tabbernor fault wne; NZ ...
... Figure 1 - Map showing main subdivisions and structural elements ofthe Trans-Hudson Orogen in northern Saskatchewan and Manitoba. Ensialic blocks are patterned; largely juvenile arc-related terranes are not. C-SBZ, Churchill-Superior Boundary Zone; HB, Hanson Lake Block; TZ, Tabbernor fault wne; NZ ...
The Río de la Plata Craton: a review of units, boundaries, ages and
... Cufré Shear Zone and is a greenschist facies folded volcano-sedimentary succession. The formation is divided into NE- and NW-trending sectors, due to the influence of conjugate NNW dextral and ENE sinistral shear zones (Fig. 2). Sedimentary lithologies include predominant metapelites and rarely dol ...
... Cufré Shear Zone and is a greenschist facies folded volcano-sedimentary succession. The formation is divided into NE- and NW-trending sectors, due to the influence of conjugate NNW dextral and ENE sinistral shear zones (Fig. 2). Sedimentary lithologies include predominant metapelites and rarely dol ...
lecture notes
... 1. Most continents consist of two major components: a relatively stable craton over which epeiric seas transgressed and regressed, surrounded by mobile belts in which mountain building took place. Four mobile belts formed around the margin of the North American craton during the Paleozoic: the Frank ...
... 1. Most continents consist of two major components: a relatively stable craton over which epeiric seas transgressed and regressed, surrounded by mobile belts in which mountain building took place. Four mobile belts formed around the margin of the North American craton during the Paleozoic: the Frank ...
Consisting of the Orange 7.5-Minute Quadrangle
... have come from the roots of an island arc. Extensive U-Pb zircon dating based on large well studied exposures (Tucker and Robinson, 1990) has yielded a total age range of 455-442 Ma. The upper age limit corresponds almost exactly to the recognized time of emplacement of the Giddings Brook slice of t ...
... have come from the roots of an island arc. Extensive U-Pb zircon dating based on large well studied exposures (Tucker and Robinson, 1990) has yielded a total age range of 455-442 Ma. The upper age limit corresponds almost exactly to the recognized time of emplacement of the Giddings Brook slice of t ...
No Slide Title
... • North America evolved by the amalgamation of Archean cratons that served as a nucleus around which younger continental crust was added. ...
... • North America evolved by the amalgamation of Archean cratons that served as a nucleus around which younger continental crust was added. ...
PDF format - gemoc - Macquarie University
... and Ellis 1996). Such melts might be trapped during a later stage of core formation when sulfide melts drained to the core, percolating through a solidified perovskite layer, whereas the molten upper mantle was cleared of all metal (Ballhaus and Ellis 1996). We suggest a similar origin for the Ni-Co ...
... and Ellis 1996). Such melts might be trapped during a later stage of core formation when sulfide melts drained to the core, percolating through a solidified perovskite layer, whereas the molten upper mantle was cleared of all metal (Ballhaus and Ellis 1996). We suggest a similar origin for the Ni-Co ...
The Archean Eon
... Late Archean: Evidence for oldest large continent with river systems • Pongola Group and Witwatersrand Supergroup, ...
... Late Archean: Evidence for oldest large continent with river systems • Pongola Group and Witwatersrand Supergroup, ...
Chapter 9
... • Laurentia originated and underwent important growth between 2.0 and 1.8 billion years ago • During this time, collisions among various plates formed several orogens – linear or arcuate deformation belts in which many of the rocks have been metamorphosed and intruded by magma ...
... • Laurentia originated and underwent important growth between 2.0 and 1.8 billion years ago • During this time, collisions among various plates formed several orogens – linear or arcuate deformation belts in which many of the rocks have been metamorphosed and intruded by magma ...
SUBMIT_1
... Permian, a united continent, so called the Pangaea, formed again as a result of the combination of Gondwana land and Laurasia land. In the process, African Plate splited away from the neighbor plates, leading to the formation of passive margin and inner plate rift activities. From the largest united ...
... Permian, a united continent, so called the Pangaea, formed again as a result of the combination of Gondwana land and Laurasia land. In the process, African Plate splited away from the neighbor plates, leading to the formation of passive margin and inner plate rift activities. From the largest united ...
this PDF file - Journal of Student Science and Technology
... convergence of tectonic plates. 1 As a result, the North America plate has grown westward. Western Canada can be divided into two main geological regions: (1) the craton, which corresponds to the ancient core of North America that has persisted for more than 1 billion years, and (2) the Cordillera m ...
... convergence of tectonic plates. 1 As a result, the North America plate has grown westward. Western Canada can be divided into two main geological regions: (1) the craton, which corresponds to the ancient core of North America that has persisted for more than 1 billion years, and (2) the Cordillera m ...
Tectonostratigraphic terranes in the Circum
... The spatial distribution of the intrusions in the Gutâi Mts. suggests a possible connection with the major transcrustal fault/ tectonic system Bogdan Vodă-Dragoş Vodă, developed in the southern part of the volcanic area, as well as with some tectonic alignments showing the same orientation as most o ...
... The spatial distribution of the intrusions in the Gutâi Mts. suggests a possible connection with the major transcrustal fault/ tectonic system Bogdan Vodă-Dragoş Vodă, developed in the southern part of the volcanic area, as well as with some tectonic alignments showing the same orientation as most o ...
Archean
... • North America evolved by the amalgamation of Archean cratons that served as a nucleus around which younger continental crust was added. ...
... • North America evolved by the amalgamation of Archean cratons that served as a nucleus around which younger continental crust was added. ...
Yilgarn Craton
The Yilgarn Craton is a large craton that constitutes the bulk of the Western Australian land mass. It is bounded by a mixture of sedimentary basins and Proterozoic fold and thrust belts. Zircon grains in the Jack Hills, Narryer Terrane have been dated at ~4.27 Ga, with one detrital zircon dated as old as 4.4 Ga.