A revision of the Proterozoic-Archean boundary of the Northern Bothnian schist belt with a discussion of the geochemistry of related basic metavolcanics [PDF]
Bulletin of the Geological Society of Finland, 1986 Geophysical analysis suggests the need for a revision of the eastern border of the early Proterozoic Northern Bothnian (or Kiiminki) schist belt. Recent geological field work has revealed places where the discordance and hiatus between Proterozoic and ...
Y. Kähkonen, E. Mattila, J. Nuutilainen
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A sluggish mid‐Proterozoic biosphere and its effect on Earth's redox balance [PDF]
Geobiology, 2018 The possibility of low but nontrivial atmospheric oxygen (O2) levels during the mid‐Proterozoic (between 1.8 and 0.8 billion years ago, Ga) has important ramifications for understanding Earth's O2 cycle, the evolution of complex life and evolving climate
K. Ozaki, C. Reinhard, E. Tajika
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When Proterozoic Crusts Became Thick: New Insights from Magma Petrology
Geosciences, 2018 The Earth’s continental crust represents the outermost envelope of the solid Earth, controlling exchanges within the geosphere and reflecting geodynamics processes.
Jérôme Ganne +7 more
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Early Ediacaran collision zone (ca. 620 Ma) in Saudi Arabia and Yemen inferred from aeromagnetic mapping [PDF]
LithosphereThe tectonic terranes in the Proterozoic outcrops in Saudi Arabia are separated from those in Yemen by extensive regions that are covered by Phanerozoic sedimentary rocks and Tertiary volcanics.
Moujahed Al-Husseini, Ian C.F. Stewart
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Archean versus Phanerozoic oceanic crust formation and tectonics: Ophiolites through time
Geosystems and Geoenvironment, 2022 A global compilation of structural, lithological, and geochemical data on a selection of Archean, Proterozoic and Phanerozoic magmatic complexes, interpreted as ophiolites, is presented.
Harald Furnes, Yildirim Dilek
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Strongly Peraluminous Granites across the Archean–Proterozoic Transition
Journal of Petrology, 2019 Strongly peraluminous granites (SPGs) form through the partial melting of metasedimentary rocks and therefore represent archives of the influence of assimilation of sedimentary rocks on the petrology and chemistry of igneous rocks.
C. Bucholz, C. Spencer
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Geologos, 2014 Numerous soft-sediment deformation structures occur within the Proterozoic Bhander Limestone of an intracratonic sag basin in a 750 m long section along the Thomas River, near Maihar, central India. Part of these deformation structures have most probably
Sarkar Subir +4 more
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The Cambrian Explosion: macroevolution and biomineralization
Academia Biology, 2023 Recent advances in our understanding of the Cambrian evolutionary diversification event (Cambrian Explosion) show that, although eumetazoan stem taxa were present in the late Proterozoic, a tremendous burst of macroevolutionary change occurred near the ...
Mark A. S. McMenamin
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The early Proterozoic Saari-Kiekki greenstone belt: A representative of the Sariola Group at Kuhmo, Eastern Finland [PDF]
Bulletin of the Geological Society of Finland, 1989 The early Proterozoic Saari-Kiekki greenstone belt in Kuhmo, eastern Finland, is the deformed remnant of a NW‒SE-trending elongate structural basin c. 15 km long and up to 3 km wide.
E.J. Luukkonen
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, 1997 The Proterozoic rocks form a major component of the supracrustal wedge in northern Yukon Territory and western District of Mackenzie. They are composed mostly of sedimentary, clastic rocks of lower greenschist facies and rest with profound unconformity upon crystalline igneous and metamorphic rocks of the Hudsonian basement.
D K Norris, L D Dyke
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