Results 31 to 40 of about 15,483 (211)
The Abundance and Behavior of Viruses in Ancient Seawater and Modern Iron-rich Environments [PDF]
, 2011 The proclivity of silica for ferric hydroxide sorption sites allows for an Archean iron cycle involving iron-silica co-precipitation and deposition of banded iron formations (BIF).
Liu, Hanna Ken-Yuin
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Drilling for the Archean Roots of Life and Tectonic Earth in the Barberton Mountains [PDF]
Scientific Drilling, 2009 In the Barberton Scientific Drilling Program (BSDP) we successfully completed three drill holes in 2008 across strategically selected rock formations in the early Archean Barberton Greenstone Belt, South Africa.
Nicola McLoughlin +3 more
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Rare-earth elements in the Archean iron formation and associated schists in Ukkolanvaara, Ilomantsi, SE Finland [PDF]
Bulletin of the Geological Society of Finland, 1977 This study describes the La, Ce, Nd, Sm, Eu, Tb, Yb and Lu concentrations in six iron-formation rocks (Fetot >> 15 %), four ferriferous schists (Fetot ~ 10—15 %) and two schist interbeds of the Archean Ukkolanvaara iron formation, as well as in seven ...
K. Laajoki, S. Lavikainen
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Archean crust-mantle geodynamic regimes: A review
Geosystems and Geoenvironment, 2022 The crust-mantle dynamic system of the formation and evolution of the early Earth crust is a frontier field in current Earth Science. This paper mainly introduces the popular dynamic models, comprising the stagnant-lid, mantle plume, sagduction, dripping,
Shuwen Liu +7 more
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, 2021 The relationship between ∆36S and ∆33S in Archean sedimentary pyrites has been used to evaluate early geologic processes, including photochemical reactions in the anoxic atmosphere, biological activity and thermochemical alteration during sediment ...
Chen, M +4 more
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Discovery of mafic impact melt in the center of the Vredefort dome:archetype for continental residua of early Earth cratering? [PDF]
, 2014 Melting by impact heating is thought to have been a significant process in the modification of early planetary crusts; however, crustally derived melt bodies in ancient terrestrial crust are frequently presumed to be absent due to erosion.
Barker, I. R. +6 more
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, 2021 Characterization of terrestrial analog sites is critical for detection and determination of clay miner-alogy in remote sensing studies of Mars aimed at geological, hydrological, and potentially biological investigations.
Janice L. Bishop +9 more
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The Sedimentary Origin of Black and White Banded Cherts of the Buck Reef, Barberton, South Africa
Geosciences, 2019 The Buck Reef is a 250−400 m thick sequence of banded black and white (B&W) cherts deposited ca. 3416 Ma ago in a shallow basin. We provide field, petrological and geochemical constraints on the chert-forming process and the origin of the ...
Morgane Ledevin +4 more
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Building Archean cratonic roots [PDF]
Frontiers in Earth Science, 2022 Geophysical, geochemical, and geological investigations have attributed the stable behaviour of Earth's continents to the presence of their Archean cratonic roots. These roots are likely composed of melt-depleted, low density residual peridotite with high Magnesium number (Mg#), while devolatilisation from the upper mantle during magmatic events might ...
Charitra Jain +6 more
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Archean continental crust formed by magma hybridization and voluminous partial melting
Scientific Reports, 2021 Archean (4.0–2.5 Ga) tonalite–trondhjemite–granodiorite (TTG) terranes represent fragments of Earth’s first continents that formed via high-grade metamorphism and partial melting of hydrated basaltic crust. While a range of geodynamic regimes can explain
Juan David Hernández-Montenegro +3 more
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