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东沙海区浅层沉积物的两个岩心出现大量的黄铁矿。GC10岩心中的黄铁矿在300 cm以下含量增加,在700 cm的区段达到最高,主要为管状、棒状、莓球状;HD319岩心黄铁矿则相对较低,只在最底部730 cm的区段突然增加,以莓球状为主。GC10岩心黄铁矿含量异常层位与甲烷含量增加层位一致,而在C_(org)-S_(sulfide)~(2-)含量变化图上,S~(2-)含量与有机碳含量线性关系不明显,显示了该岩心黄铁矿的形成主要受高甲烷流通量影响;而HD319岩心的有机碳高的层位,S~(2-)含量也高,表明HD319岩心黄铁矿的形成与沉积物中有机质降解密切相关。GC10岩心黄铁矿的δ~(34)S(‰)值在-17.149～-33.240 CDT之间,显示了非常负的硫同位素比值和宽的区间;HD319的δ~(34)S(‰)值-36.363～-39.162 CDT之间,相对比较稳定。GC10岩心黄铁矿的δ~(34)S(‰)值特征,可能与富甲烷环境有关,而HD319受其影响稍弱。
There are a large number of pyrites in the two cores of the shallow sediments in the Dongshahai Sea. The content of pyrite in GC10 core increased below 300 cm and reached the highest in the 700 cm section, mainly in the shape of tube, rod and raspberry. HD319 core pyrite was relatively low, only in the bottom 730 cm Section suddenly increased to raspberry-based. In the GC10 ore core, the anomalous horizon of pyrite content is consistent with the increase of methane content, while the content of S ~ (2-) and the content of organic carbon in the org-sulfide ~ (2-) The relationship is not obvious, which shows that the formation of pyrite in this core is mainly affected by the high methane flux. However, the high organic carbon layer of HD319 core also has a high content of S 2 2-, which indicates the formation of HD319 core pyrite It is closely related to the degradation of organic matter in sediments. The δ ~ (34) S (‰) values of GC10 core pyrite ranged from -17.149 to -33.240 CDT, showing very negative S isotopic ratios and wide intervals. The δ ~ (34) S (‰) Value -36.363 ~ -39.162 between CDT, relatively stable. The δ ~ (34) S (‰) value of GC10 core pyrite may be related to methane-rich environment, while HD319 is slightly weaker.