Carbon isotope evidence of gas hydrate dissociation in South China Sea

被引:4
|
作者
Wang S.-H. [1 ,2 ]
Yan W. [1 ,2 ]
Chen Z. [1 ,2 ]
Chen M.-H. [1 ]
Song H.-B. [2 ,3 ]
机构
[1] Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Acad. of Sci.
[2] Guangzhou Center for Gas Hydrate Research, Chinese Acad. of Sci.
[3] Institute of Geology and Geophysics, Chinese Acad. of Sci.
关键词
Carbon isotope; Gas hydrates; South China Sea;
D O I
10.3799/dqkx.2010.068
中图分类号
学科分类号
摘要
High-resolution carbon and oxygen isotope analysis for cores NS93-5 and NS97-37 from southern South China Sea (SCS) shows the rapid negative excursion of carbon isotope in the last deglaciation (about 18 ka) and the penultimate deglaciation (about 130 ka). In the same layer, the oxygen isotope also displays similar phenomena. It is found that the Globigerinoides rubber (Pink) died out in midpoint of MIS 5/6 (about 129.84 ka). The change of carbon and oxygen isotope is in consonance with atmospheric methane concentration from the Vostok ice core. The two rapid negative excursions of carbon isotope recorded in SCS are likely related to gas hydrate dissociation, i.e. the changes of temperature and pressure induced gas hydrate dissociation and released methane in SCS and/or other areas, which made the climate warmer, ocean anoxic and further led to the extinction of some marine organism and accelerated glacial termination.
引用
收藏
页码:526 / 532
页数:6
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