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标题：Late Jurassic ocean anoxic event: evidence from voluminous sulphide deposition and preservation in the Panthalassa
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作者：Tatsuo Nozaki ; Yasuhiro Kato ; Katsuhiko Suzuki 等
期刊名称：Scientific Reports
电子版ISSN：2045-2322
出版年度：2013
卷号：3
DOI：10.1038/srep01889
出版社：Springer Nature
摘要：The historically productive copper-bearing Besshi-type sulphide deposits in the Japanese accretionary complex were formed as volcanogenic massive sulphide deposits on the deep-sea floor of the Panthalassa Ocean. Here we report that eleven typical Besshi-type deposits yielded Re-Os isochron ages around 150 Ma (148.4 ± 1.4 Ma from the composite isochron) in Late Jurassic time. This date coincides with the lowest marine ⁸⁷Sr/⁸⁶Sr ratio and highest atmospheric CO₂ concentration of the past 300 million years. We infer that intense mid-ocean ridge hydrothermal and volcanic activity in the Late Jurassic produced huge sulphide deposits and large emissions of CO₂ gas, leading to global warming and a stratified Panthalassa Ocean with anoxic deep seas that favored preservation of sulphides in the pelagic environment. The emergence of ocean anoxia triggered by seafloor volcanism is also consistent with a positive δ¹³C excursion and widespread deposition of petroleum source rocks and black shales.