Greenstone burial–exhumation cycles at the late Archean transition to plate tectonics [PDF]
Nature Communications, 2022 Supracrustal rocks of the Yilgarn orogen underwent deep burial, and later syn-shortening exhumation. Archean exhumation processes were likely less efficient that today, so that complete exhumation of high-pressure rocks was rare and accidental.
Zibra Ivan +11 more
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Insights into early continental crust formation from the most ancient heart of Scotland [PDF]
Nature CommunicationsThe paucity of rocks from Earth’s first billion years (4.5–3.5 Ga) limits understanding of early felsic (continental) crust formation and craton development.
Silvia Volante +11 more
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Geosystems and GeoenvironmentThe mineral chemistry of Fe-Mg biotite has served as an aid to the petrogenesis of igneous rocks, especially for identifying the parent magma compositions. Though the interpretation of igneous and metamorphic processes utilizing biotite mineral chemistry
Parita K. Gorania +4 more
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Age of the Tokkalehto metagabbro and its significance to the lithostratigraphy of the early Proterozoic Kuusamo supracrustal belt, northern Finland [PDF]
Bulletin of the Geological Society of Finland, 2001 The c. 30-km2 Tokkalehto metagabbro and associated sills and dykes intrude a large part of the western part of the early Proterozoic Kuusamo supracrustal belt in northern Finland. These rocks have previously been mapped as a metavolcanic unit, Greenstone
P.M. Evins, K. Laajoki
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Multi-method characterization of rare blue quartz-bearing metavolcanic rocks of the Rio dos Remédios Group, Paramirim Aulacogen, NE Brazil [PDF]
Brazilian Journal of Geology, 2023 The Rio dos Remédios Group comprises a supracrustal sequence that occupies the base of the Espinhaço Supergroup, São Francisco Craton, Brazil. Its basal formation, Novo Horizonte, crops out in the Paramirim region mainly as metavolcanic rocks that ...
Danielle Cruz da Silva +4 more
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Structural observations and U-Pb mineral ages from igneous rocks at the Archaean-Palaeoproterozoic boundary in the Salahmi Schist Belt, central Finland: constraints on tectonic evolution [PDF]
Bulletin of the Geological Society of Finland, 1999 The study area in Vieremä, central Finland, contains part of Archaean-Palaeoproterozoic boundary. In the east, the area comprises Archaean gneiss and the Salahmi Schist Belt. The rocks of the schist belt are turbiditic metagreywackes, with well-preserved
K. Pietikäinen, M. Vaasjoki
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Earth's Earliest Phaneritic Ultramafic Rocks: Mantle Slices or Crustal Cumulates?
Geochemistry, Geophysics, Geosystems, 2022 When plate tectonics initiated remains uncertain, partly because many signals interpreted as diagnostic of plate tectonics can be alternatively explained via hot stagnant‐lid tectonics.
Jiawei Zuo +10 more
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Peculiar features of the supracomplexes formation in the Keivy domain
Vestnik MGTU, 2021 The Keivy domain (the northeastern part of the Arctic zone of the Fennoscandian Shield) during the period of the maximum manifestation of the Late Archean collisional processes was overlapped by tectonic allochthons of adjacent microcontinents thrust ...
Kozlov N. E. +3 more
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The Himmerkinlahti member: An indicator of intra-karelian erosion within the early Proterozoic Kuusamo Belt, Posio, northern Finland [PDF]
Bulletin of the Geological Society of Finland, 2000 The paper establishes the Himmerkinlahti Member, which is a thin metamorphosed conglomerate-sandstone unit within the middle part of the early Proterozoic (Karelian) supracrustal sequence of the Kuusamo Belt, northern Finland.
K. Laajoki
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Geology and Lithogeochemistry of the Supracrustal Sequence and Interlayered Metabasites of NE Santos Dumont Region (MG) [PDF]
Anuário do Instituto de Geociências, 2017 The region near Santos Dumont town consists of a sequence of interlayered metabasic rocks and supracrustal gneisses. Two lithological units were individualized based on geological-structural mapping (1:50,000), petrography and lithogeochemistry: a ...
Renata Hiraga +5 more
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