Results 51 to 60 of about 2,007 (165)
The Neoproterozoic to Early Cambrian period is a very important era in the history of earth evolution. Research on stratigraphic framework, paleo-oceanography, palaro-atmospheric, and paleoclimatology are focuses of international geosciences.
WANG Fu-liang +7 more
doaj +1 more source
ABSTRACT In the Recôncavo Basin, Northeast of Brazil, mud diapirs have been reported for decades, but their role within the basin's petroleum system remains poorly constrained. Here, we combine 2D seismic interpretation, field observations, and organic geochemical analyses of rocks and oil seeps to investigate the relationship between diapirism and ...
Cora Mattos +3 more
wiley +1 more source
MINERALOGY AND ZIRCON AGE OF CARBONATITES OF THE SREDNYAYA ZIMA COMPLEX (EASTERN SAYAN)
The Srednyaya Zima alkaline-ultramafic carbonatite complex is located in the Eastern Sayan and is a part of the area of manifestation of Neoproterozoic rare-metal alkaline-carbonatite magmatism along the southern and southeastern margins of the Siberian ...
I. R. Prokopyev +5 more
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3D inversion of the Sichuan Basin magnetic anomaly in South China and its geological significance
The Sichuan Basin magnetic anomaly is the most striking regional aeromagnetic anomaly in South China. It is characterized by a continuous large-scale linear magnetic anomaly and contains long-wavelength constituents which could still be detected on ...
Jie Wang +6 more
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ABSTRACT Deep crustal fragments and structural lineaments identified through satellite gravity data provide evidence for the extension of the reworked ancient basement of the Central African Block into the northern São Francisco Craton and southern Borborema Province.
Douglas Teixeira Martins +3 more
wiley +1 more source
Cryogenian Glacial Erosion and Tectonics as Agents of Crustal Recycling
ABSTRACT Zircon preserves evidence of recycling processes that link surface environments to the mantle. Combined δ18O‐εHf in zircon fingerprints magmatic sources and tracks how crustal material is reworked over time. We apply statistical analyses to a global compilation that apparently resolves shifts in zircon U–Pb, δ18O, and Lu‐Hf data spanning the ...
M. Seraine +9 more
wiley +1 more source
ABSTRACT The Transbrasiliano‐Kandi‐4°50′ (TK4) shear zone in western Gondwana crosscuts South America and NW Africa for at least 6000 km. Despite its impressive size, the timing of the main episode of dextral ductile shearing is uncertain. We present detailed in situ multi‐mineral geochronology of mylonites from both Brazil and Algeria supporting that ...
F. A. Caxito +4 more
wiley +1 more source
Charnockites with 2691–2607 Ma magmatic ages from the NMZ show arc‐magmatic geochemical signatures. They correspond to the lower‐crustal equivalent of the Chilimanzi Suite Granite in the Zimbabwe Craton. Lu‐Hf isotopic data of magmatic zircons show negative εHf(t) values (−11.18 to −2.20) with TDMC ages of 3699–3158 Ma, suggesting their protolith ...
Toshiaki Tsunogae +6 more
wiley +1 more source
Provenance studies are helpful in reconstructing the tectonic, climatic and geographic setting of terrigenous sedimentary basins. The primary controls on the composition of detrital sedimentary rocks are the composition, climate and relief conditions of ...
André Weissheimer de Borba +4 more
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The first animals: ca. 760-million-year-old sponge-like fossils from Namibia
One of the most profound events in biospheric evolution was the emergence of animals, which is thought to have occurred some 600-650 Ma. Here we report on the discovery of phosphatised body fossils that we interpret as ancient sponge-like fossils and ...
C. Brain +9 more
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