甲烷水合物是地球沉积圈最大的可交换碳储库,在全球变暖和海平面变化期将大规模分解释放,对全球气候和环境产生重大影响.新元古代极端寒冷的冰期之末可能发生了地史上最大的甲烷水合物分解释放事件.Marinoan冰后期(约635Ma)盖帽碳酸盐岩中广布的甲烷渗漏构造、特殊的同位素标识、低硫酸盐浓度、海相重晶石沉积以及短暂而显著的碳同位素负漂(δ13C≤?5‰)提供了新元古代晚期冰川消融和海进过程中甲烷释放的有力证据.甲烷释放可能导致了全球变暖,促进了全球冰川迅速融化;而甲烷氧化导致的海洋缺氧和大气含氧量波动可能是新元古代末后生动物演化的重要环境驱动因素.该事件有待进一步研究的问题包括:甲烷水合物分解释放的诱发因素、甲烷最初释放与海洋缺氧事件发生的时间及其与生物演化之间的关系、反映甲烷氧化的地球化学信号、盖帽碳酸盐岩的区域和全球等时性等.华南陡山沱组底部的盖帽碳酸盐岩提供了研究这些问题的良好实例. Methane hydrate is the largest exchangeable carbon deposit in the Earth’s sedimentary circle and will be largely decomposed and released during global warming and sea-level change, which will have a significant impact on the global climate and environment. The end of the Neoproterozoic extreme cold glacial period may occur The history of the largest methane hydrate decomposition release event.Marinoan ice in the late (about 635Ma) cap carbonate widely distributed in the methane leakage structure, special isotope identification, low sulfate concentration, marine barite deposition and transient The significant carbon isotope negative bleaching (δ13C≤5 ‰) provides strong evidence of the late Neoproterozoic glacier ablation and methane release during the sea-in. The release of methane may lead to global warming and promote the rapid melting of the glacier in the world. Marine hypoxia caused by methane oxidation and fluctuations of atmospheric oxygen content may be important environmental drivers for the evolution of Neoproterozoic post-zozoic animals.The issues to be further studied in this event include: the predisposing factors for methane hydrate decomposition and release, the initial methane release and The timing of the occurrence of marine hypoxic events and their relationship to the biological evolution reflects the geochemical signals of methane oxidation, capped carbon When regional and global rock salt, etc. The cap carbonate rocks at the bottom of a steep hill in southern Da group provides a good case study of these issues.