海底冷泉流体渗漏的原位观测技术及冷泉活动特征

海底冷泉渗漏是海洋环境中广泛分布的自然现象.本文主要介绍海底冷泉原住观测技术及全球几个典型冷来渗漏活动地区的原位观测结果.冷泉渗漏活动主要发育在海底裂隙和断层发育的地区,海底常有泥火山、麻坑、水合物、冷泉生物群落和冷泉碳酸盐岩的发育.冷泉渗漏主要包括液体和气体两种形式,流体流动包括上升流和下降流两种方式,流量变化大,主要与海底环境及构造作用有关.烃类渗漏是以气泡、油滴的形式沿断层向海底喷溢,释放量大,运移过程主要受涌浪、静水压力和裂隙压力等因素控制.冷泉渗漏活动是复杂的水文地质过程,受水合物形成和分解产生的气藏的充注和排空、深部常规油气藏的破坏及海底环境变化等多种作用的控制.

In situ measurement of fluid flow and signatures of seep activity at marine seep sites

Cold seepage is a widely observed phenomenon in marine environment worldwide. This paper focuses on a review of the in situ measurement of cold seep and its results of several typical active cold seeps in the world. Seepage activity is generally associated with the seafloor fractures and faults. Mud volcanes, pockmarks, hydrate, cold seep communities, and seep carbonate are common at the seep sites. Basically, there are two types of fluids, liquid and gas, and two modes of fluid flow, upward and downward flow at seep sites. The flux of fluid changes greatly, which is usually controlled by the geological settings. Hydrocarbon seepage erupts along a fault to seabed as bubbles and oil drops, releasing large amount of hydrocarbons. This process is controlled mainly by swell, hydrostatic pressure, and fracture pressure and so on. Seepage activity is a complicated hydrogeology process that is mainly correlated with hydrate formation and decomposition related to the filling and emptying of gas reservoir, destruction of deep oil and gas reservoir, and submarine environmental change.