天然气水合物分解诱发海底滑坡的实验研究

As a type of new energy resource, the reserves of gas hydrates is enormous and untapped currently, which is considered as one of alternative energy in the future. However, submarine landslides has an important influence on the security of marine resource exploration and development. Gas hydrates dissociation is a critical factor for the occurrence of submarine landslides. So this project studies on the submarine landslides mechanism due to gas hydrate dissociation. First, the typical landslide geological models and patterns will be established by geophysical data. Secondly, slope stability experiments will be conducted for simulating submarine landslides due to gas hydrate dissociation. The appropriate similar material will be chosen to instead of geological mass, and landslide formation and sliding process will be monitor based on digital speckle method. Finally, we will analyze the dynamic mechanism of submarine landslides and disaster influence scope and evaluate comprehensively gas hydrate stability of mining area according to experiment results.

天然气水合物是目前尚未开发的储量巨大的一种新能源，而海底滑坡对于海洋资源勘探开发的安全有着重要影响。其中海底水合物分解是诱发部分海底滑坡的一个关键因素。本项目利用地球物理资料，对国内外典型的水合物分解诱发的海底滑坡灾害进行研究，获取典型的滑坡地质模型和发生模式，从物理模拟角度，使用海底斜坡稳定性分析实验系统，选用合适的相似材料对海底滑坡演化过程进行物理模拟，运用数字散斑方法研究海底滑坡的形成、滑动过程，初步揭示由水合物分解产生海底滑坡的动力机制及灾害影响范围，综合评价天然气水合物成矿区稳定性。

水合物资源成藏与海底滑坡灾害效应的研究，对于认识水合物富集成藏机制与资源勘探开发具有重要的参考和应用价值。本项目以南海北部陆坡的资源能源灾害效应为研究对象，探讨了该地区洋陆转换带的深部构造特征；分析了BSR分布与活动构造的关系，同时分析了研究区的滑坡类型特征及触发机制，并研制了海底滑坡模拟系统进行实验，研究了水合物分解与海底滑坡的关系。通过水合物分解模拟实验可以看出，水合物分解会降低斜坡的稳定性，但不一定导致斜坡失稳。总位移、水平位移和竖向位移最初随着水合物分解量的增大而增大。滑动面沿着水合物层顶层发育。