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Showing 1 to 20 of 27 for “"supercontinent"”.
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Investigating the metamorphic evolution of reworked terrains.
… thesis can be used as constraints for models of supercontinent evolution Two different regions are targeted in this study. The first region is the Palaeo- to Mesoproterozoic rocks of the Gawler Craton. These rocks have experienced extensive granulite facies metamorphism at c. 1690 - 1665 and 1590 …
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Supercontinental Inheritance and its Influence on Supercontinental Breakup: The Central Atlantic Magmatic Province and the Breakup of Pangea
… (LIP) that coincides with the breakup of the supercontinent Pangea. Major and trace element data, Sr-Nd-Pb radiogenic isotopes, and high-precision olivine chemistry were collected on primitive CAMP dikes from Virginia (VA). These new samples were used in conjunction with a global CAMP data set …
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Tectono-thermal evolution of Gjelsvikfjella, Western Dronning Maud Land, Antarctica
… been used as a piercing point in Mesoproterozoic supercontinent reconstruction. However, with the growing number of geochronological data pointing to major structural reworking and not just a thermal overprint of the Mesoproterozoic crust during the Pan-African orogeny thereby challenging early …
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Monazite Geochronology of the Madison Mylonite Zone and Environs, Southwestern Montana: With Implications for Precambrian Thermotectonic Evolution of the Northern Wyoming Province
… Wyoming craton may have been the final stages of supercontinent Kenorland assembly, whereas the ~2450 Ma reactivation, recorded by monazite rim growth, along the SSZ-MMZ may relate to the incipient supercontinent break-up, which has been suggested to have occurred at about this time by other …
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From Gondwanaland, with love : the tale of how Boston got its rocks
… at the South Pole, as the northern coast of a supercontinent called Gondwanaland. Boston's journey from the South Pole to its current location traces the world's geologic history over that period of time, including the emergence of animal life as we know it, the formation and destruction of …
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Mesoproterozoic Basement From The Central And Southern Appalachians Reveal High-temperature Magmatic Conditions And Non-laurentian Origin Of Earth’s Most Zircon Fertile Magmas
… Grenville Orogeny led to the formation of the supercontinent Rodinia. One unique characteristic of the Grenville Orogeny is that it produced a volumetrically significant amount of zirconium- (Zr) enriched granitoids, evidently more than any period both prior to and after the Grenville. To …
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Mesoproterozoic Basement From the Central and Southern Appalachians Reveal High-temperature Magmatic Conditions and Non-laurentian origin of Earth's Most Zircon Fertile Magmas
… Grenville Orogeny led to the formation of the supercontinent Rodinia. One unique characteristic of the Grenville Orogeny is that it produced a volumetrically significant amount of zirconium- (Zr) enriched granitoids, evidently more than any period both prior to and after the Grenville. To …
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A lower crustal perspective on the stabilization and reactivation of continental lithosphere in the western Canadian shield
… coincides with the assembly of the Laurentian supercontinent. The correlation of 1.9 Ga mafic magmatism and metamorphism in the Chipman domain with contemporaneous mafic magmatism along > 1200 km strike-length of the Snowbird tectonic zone indicates that regional asthenospheric upwelling was an …
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Geological constraints on Neoproterozoic glacial episodes
… in the Earth System, such as the breakup of a supercontinent, the evolution of complex multicellular life and extreme geochemical perturbations. A Neoproterozoic stratigraphic scheme has been developed over the last thirty years that uses these major glacial episodes for correlation, yet …
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Archean detrital zircons in the Proterozoic Vishnu Schist of the Grand Canyon, Arizona : implications for crustal architecture and Nuna reconstructions
… for viable reconstructions of the Nuna supercontinent. However, given the high percentage of pre-1.8 Ga zircons, unexposed proximal basement sources are more likely, resulting in a model by which Vishnu sediments were derived from Mojave crust that consists of Archean and 1.9-1.8 Ga …
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Stratigraphy and Depositional Characterization of the Moorefield Shale (Middle-Late Mississippian) in its Type Area, Northeastern Arkansas (Eastern Arkoma Basin)
… it’s collision with Gondwanaland to form the supercontinent Pangea at the end of the Paleozoic. During this time, the midcontinent region was covered by shallow seas and carbonates covered most of the region. A shallowly dipping carbonate ramp developed in the region providing a foundation for …
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Electrofacies, elemental composition, and source rock characteristics along seismic reflectors of the Vaca Muerta Formation in the Loma La Lata area, Neuquen Basin, Argentina
… during and after the break-up of the Gondwana supercontinent. The Vaca Muerta was recognized and named in early stratigraphic studies of the basin in the 1930s. The production of hydrocarbons in the basin led to subsequent detailed studies of the formation, primarily as an important source …
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The geochemistry and geochronology of the barby formation in the sinclair area, Southern Namibia
… took place during the assembly of the Rodinia supercontinent. It is slightly younger at 1204 ±9 Ma and reflects the end of subduction-related volcanism due to the collision of Namaqua terranes with the Konkiep Terrane. The Spes Bona syenite and the Barby units have Lu-Hf crustal residence ages …
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Petrogenetic and Geochemical characterization of the Spinghar Crystalline Complex in North-Western Pakistan
… plate during the Paleoproterozoic Columbia supercontinent assembly that extends across the Himalayan belt.
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Biogeochemical proxies for environmental and biotic conditions at the Permian-Triassic boundary
… sea situated in the northwest of the supercontinent Pangaea. The Great Bank of Guizhou, China is the third section studied, and it is a carbonate platform deposited on the southern edge of one of the smaller continental blocks that formed the eastern margin of the Paleo-Tethys Ocean. …
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The Neoproterozoic São Francisco Basin, central Brazil: tectonic evolution, paleoclimate, and mineral systems
… sediments, accumulated during breakup of the supercontinent Rodinia. Deposition was punctuated by globally correlative Sturtian glacial deposits (ca. 717-660 Ma). Copious post-glacial organic matter and pyrite-rich siltstones formed during the subsequent passive margin stage. The overlying …
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DETRITAL-ZIRCON GEOCHRONOLOGIC PROVENANCE ANALYSES THAT TEST AND EXPAND THE EAST SIBERIA - WEST LAURENTIA RODINIA RECONSTRUCTION
Laurentia's position in the Neoproterozoic supercontinent Rodinia is a topic of continuing debate. Several reconstructions involving Laurentia and Siberia have been proposed, including the east Siberia-west Laurentia connection. The east Siberia-west Laurentia Rodinia reconstruction includes …
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DETRITAL-ZIRCON GEOCHRONOLOGIC PROVENANCE ANALYSES THAT TEST AND EXPAND THE EAST SIBERIA - WEST LAURENTIA RODINIA RECONSTRUCTION
Laurentia's position in the Neoproterozoic supercontinent Rodinia is a topic of continuing debate. Several reconstructions involving Laurentia and Siberia have been proposed, including the east Siberia-west Laurentia connection. The east Siberia-west Laurentia Rodinia reconstruction includes …
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Pseudoscorpion Systematics & Phylogenetics: Exploring the Effects of Accelerated Rates of Evolution on Both Ancient and Recent Diversification
… the coming together and breaking apart of the supercontinent Pangea, the rise and fall of the Dinosaurs, and many iterations of extreme global climatic fluctuations. Roughly 400 million years of diversification and extinction have resulted in 4,359 currently described extant pseudoscorpion …
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Oroclines of the Iberian Variscan belt: Tectonic and paleogeographic implications
… that culminated with the amalgamation of the supercontinent Pangea. The Iberian segment of the Variscan belt is characterized by Cantabrian orocline, which is 180º and convex toward the west. Several lines of evidence are at odds with classical interpretation of the Cantabrian orocline as the …
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