A palaeogeographic context for Neoproterozoic glaciation
نویسندگان
چکیده
منابع مشابه
Biomarker evidence for photosynthesis during neoproterozoic glaciation.
Laterally extensive black shales were deposited on the São Francisco craton in southeastern Brazil during low-latitude Neoproterozoic glaciation approximately 740 to 700 million years ago. These rocks contain up to 3.0 weight % organic carbon, which we interpret as representing the preserved record of abundant marine primary productivity from glacial times. Extractable biomarkers reflect a comp...
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Two separate and distinct diamictite-rich units occur in the mixed carbonate-siliciclastic PolarisbreenGroup, which comprises the top kilometer of47 km of Neoproterozoic strata in the northeast of the Svalbard archipelago.The platformal succession accumulated on the windward, tropical to subtropical margin of Laurentia.The older PetrovbreenMember is a thin glacimarine diamictite that lacks a ca...
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The Neoproterozoic Quruqtagh Group in eastern Chinese Tianshan consists of, in ascending order, the Bayisi, Zhaobishan, Altungol, Tereeken, Zhamoketi, Yukkengol, Shuiquan, and Hankalchough Formations. Diamictite units occur in the Bayisi–Altungol, Tereeken, and Hankalchough Formations. Our field observations confirm the glacial origin of the Tereeken and Hankalchough diamictites, but the glacia...
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[1] A large (11–15%) negative shift in dC is observed in shallow water carbonates directly beneath Neoproterozoic glacial deposits (or correlative disconformity) in northwest Namibia ascribed to a snowball Earth. Reproducibility and stratigraphic concordance of this anomaly in 16 sections across the ancient continental shelf support a primary origin, and field relations show it predates the fal...
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ژورنال
عنوان ژورنال: Palaeogeography, Palaeoclimatology, Palaeoecology
سال: 2009
ISSN: 0031-0182
DOI: 10.1016/j.palaeo.2009.03.013