南海北部神狐海域天然气水合物差异性分布的控制因素

南海北部陆坡区具备天然气水合物形成聚集的地质条件,神狐海域的海底沉积层温度和压力条件符合水合物成藏的要求;源岩生烃潜力巨大且烃类运移条件良好,可以为水合物成藏提供充足的气源和通畅的运移通道。然而,钻探结果揭示了神狐海域天然气水合物在相似地质背景地区聚集分布的差异性,其机理及控制因素并不清楚。基于研究区8口钻探井的成藏地质条件,综合对比分析了成功获取及未获取水合物站位处的地震、测井、钻井、地球化学等数据,并以此探究南海北部神狐地区天然气水合物分布不均匀性的控制和影响因素。

DIFFERENTIATED DISTRIBUTION OF METHANE HYDRATE IN THE SHENHU AREA OF THE NORTHERN SOUTH CHINA SEA AND CONTROLLING FACTORS

Geological conditions, in particular temperature and pressure, are favorable for gas hydrate accumulation in the Shenhu area on the northern slope of the South China Sea. Source rocks having great potential for gas-generation and effective pathways for hydrocarbon migration are available as well. However, drilling results suggest that great difference occurs in different locations in the Shenhu area in terms of gas hydrate accumulation. So far the mechanism and control factors have remained unknown. In this paper, data from 8 drilling wells, including seismic, logging, drilling and geochemical data, are collected and a comparative study conducted on gas hydrate accumulation conditions for both the succeeded and failed wells in order to find the reason for the different distribution of natural gas hydrate in the Northern South China Sea.