西非深水JDZ-2-1井钻井工程整体风险分析

Affecting factors research on the risks of deep water drilling operation in West Africa

由于深水钻井具有高投资、高风险的特点,在西非深水JDZ-2-1井钻前对其进行风险评价,对做好应急备案具有重要意义。分别阐述了雷暴、暴风、波浪、潮汐、雾、水深、水下洋流、浅层地质灾害、天然气水合物、异常压力、狭窄的地层孔隙/破裂压力窗口和地震因素等对深水钻井作业的影响及危害,并结合JDZ-2区块的实际自然环境和地质条件,利用层次风险评价方法(APH),按照深水钻井常规作业的组成部分,建立钻井工程整体风险层次结构,对其进行整体风险评价。分析结果表明,JDZ-2-1井在钻井液性能受到各因素的影响较为明显时,其风险值最大,而钻进作业、取心和测井作业风险次之。该分析研究为制定应对风险的措施提供了参考。

Because of the high investment and high risk characteristic of drilling operation in deep water, pre-drilling risk evaluation was completed for the deep water Well - JDZ-2-1 in West Africa, it has significant benefits for emergency response. The influences of thunder storm, hurricane, wave, tide, fog, water depth, submarine ocean current, shallow geologic hazards, gas hydrate, abnormal pressure, narrow pore pressure/fracture pressure window and earthquake to the deep water drilling operation are covered in this paper. The real natural environment and geologic conditions of JDZ-2 Block was also considered when build up and evaluate the integrated risk hierarchical structure of drilling operation by using the Analytical Hierarchy Process （ APH ） method as per the normal component parts of conventional drilling operation in deep water. According to the analysis results, the influence of different factors to drilling fluid are significant and has the highest risk, the risk of drilling operation, coring operation and logging is lower. This analysis and research provided good reference for the selection of risk associated measures.