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通过南海南部NS93-5和NS97-37两个柱状沉积物的高分辨率碳、氧同位素分析发现,末次冰消期(约18ka)和倒数第二次冰消期(约130ka)记录到了碳同位素的快速负偏移现象,与此同时,氧同位素也发生了明显的快速负偏移,气温快速回升,并在氧同位素5期与6期过渡中点(约129.84ka)出现粉红色红拟抱球虫灭绝现象,而且两柱样碳、氧同位素的变化趋势与Vostok冰心记录到的大气甲烷含量的变化基本一致.分析认为,南海记录到的最近2个冰期结束时的碳同位素快速负偏移很可能与天然气水合物的分解释放有关,即外界温压条件的变化可能导致了南海和/或其他地区海底天然气水合物的失稳分解并释放甲烷,从而使气候快速变暖、导致海洋缺氧和某些生物种类的灭绝,同时也加快了冰期的终止.
High-resolution carbon and oxygen isotope analyzes of two columnar sediments from NS93-5 and NS97-37 in the southern South China Sea revealed that the carbon isotopes were recorded in the last ice depletion (about 18 ka) and the penultimate ice extinction (about 130 ka) At the same time, the oxygen isotopes also showed a rapid negative excursion, and the temperature rose rapidly. In the middle of the transition period of oxygen isotope 5 and 6 (about 129.84 ka) The extinction phenomena of coccidia and coccus were also consistent with the change of atmospheric methane content recorded by Vostok Bingxin.The analysis shows that the carbon isotope recorded by the South China Sea at the end of the last two glacial cycles is rapidly negatively biased It is probably related to the decomposition and release of natural gas hydrate, that is, the change of external temperature and pressure conditions may lead to the instable decomposition and release of methane in the seafloor gas hydrate in the South China Sea and / or other regions, so that the climate is rapidly warmed, And some species of extinction, but also accelerated the termination of the ice age.