Oceanic Euxinia in Earth History: Causes and Consequences

Annual Review of Earth and Planetary Sciences (Impact Factor: 8.58). 05/2008; 36(1):251-88. DOI: 10.1146/


Euxinic ocean conditions accompanied significant events in Earth history, including several Phanerozoic biotic crises. By critically ex-amining modern and ancient euxinic environments and the range of hypotheses for these sulfidic episodes, we elucidate the primary factors that influenced the generation of euxinia. We conclude that periods of global warmth promoted anoxia because of reduced sol-ubility of oxygen, not because of ocean stagnation. Anoxia led to phosphate release from sediments, and continental configurations with expansive nutrient-trapping regions focused nutrient recycling and increased regional nutrient buildup. This great nutrient supply would have fueled high biological productivity and oxygen demand, enhancing oxygen depletion and sulfide buildup via sulfate reduc-tion. As long as warm conditions prevailed, these positive feedbacks sustained euxinic conditions. In rare, extreme cases, euxinia led to biotic crises, a hypothesis best supported by evidence from the end-Permian mass extinction.

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Available from: Lee R. Kump, Jan 01, 2014
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    • "Please cite this article in press as: Lash, G.G., Pyritization induced by anaerobic oxidation of methane (AOM) e An example from the upper devonian shale succession, western New York, USA, Marine and Petroleum Geology (2015), conditions under which marine deposits accumulated (Wilkin et al., 1996; Wignall and Newton, 1998; Meyer and Kump, 2008). Where possible, diameters of at least 100 framboids from each sample were measured. "
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    Full-text · Article · Oct 2015 · Marine and Petroleum Geology
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    • "As a consequence, derivative proxies have been applied to reconstruct past ocean oxygenation. A characteristic feature of marine low-oxygen environments on various time scales are black, organic-rich, and laminated sediments (Kemp, 1996; Meyer and Kump, 2008). They are known to date back to the late Precambrian (Tucker, 1983). "
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    Full-text · Article · Feb 2015 · Biogeosciences
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