Indian margin methane hydrate dissociation recorded in the carbon isotopes of benthic (Miliolida) foraminifera
Indian margin methane hydrate dissociation recorded in the carbon isotopes of benthic (Miliolida) foraminifera
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DOI：
10.1016/j.epsl.2023.118101
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发表时间：
2023-05
影响因子：
5.3
通讯作者：
S. Clemens;K. Thirumalai;D. Oppo
中科院分区：
文献类型：
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作者：
S. Clemens;K. Thirumalai;D. Oppo
海洋沉积物中的甲烷水合物已经在不同的时间尺度上进行了研究，使用了广泛的指标，以更好地了解水合物动力学和气候的联系。在这里，我们报告个人的底栖和浮游有孔虫同位素分析在三个站点从不同的海洋环境在北方印度洋。多物种、多地点分析确定了Miliolida底栖有孔虫Pyrgo spp.独特的δ 13 C响应，Quinqueloculina spp.，和螺旋藻属（Spiroloculina spp.）这表明这些属中的某些物种在其骨骼（测试）材料的稳定碳同位素组成中记录了过去甲烷水合物分解的位置和时间。我们的研究结果表明，解离发生在Mahanadi近海盆地，孟加拉湾西北部，在过去150万年的冰期，过渡期和间冰期。更负的测试δ 13 C与更正的δ 18 O相结合，支持间冰期解离的推断，可能是由中间水温升高驱动的。
Methane hydrates in ocean sediments have been investigated across various timescales using a broad array of indicators to better understand hydrate dynamics and climate linkages. Here we report individual benthic and planktonic foraminiferal isotopic analyses at three sites from distinct oceanic environments in the northern Indian Ocean. The multi-species, multi-site analyses identify a unique δ 13 C response in Miliolida benthic foraminifera Pyrgo spp., Quinqueloculina spp., and Spiroloculina spp. suggesting that some species within these genera record the location and timing of past methane hydrate dissociation in the stable carbon isotopic composition of their skeletal (test) material. Our results document that dissociation occurred in the Mahanadi offshore basin, northwest Bay of Bengal, during glacial, transitional, and interglacial intervals of the past 1.5 million years. More negative test δ 13 C coupled with more positive δ 18 O supports the inference of interglacial-age dissociation, likely driven by increased intermediate water temperatures.