超深水超浅层探井开阔海域电缆测井技术与实践

Study and practice of wireline logging technology in open sea area for ultra-deep water and ultra-shallow exploration wells

摘要:

超深水钻井过程中，开阔海域作业能有效降低作业成本。但受超深水超浅层环境的影响，面临着浅水涌浪引起电缆测井仪器摇摆、电缆测试仪器“进洞”困难和开阔海域作业井下安全隐患大等困难和挑战。对此，针对性下入20 in套管封隔浅层涌浪，形成有效封隔；充分利用水下机器人（ROV）的辅助作用，保障仪器成功“入洞”；严格控制仪器起下速度，采用“水下ROV+平台控制面板”双重监测模式，确保作业安全。在南海琼东南盆地的多口超深水探井成功开展了多趟电缆测井作业，获取了详细的测井资料，同时大幅度降低了作业成本。该作业实践为后续超深水开阔海域作业积累了宝贵的经验，为海洋油气勘探开发增储上产、降本增效提供了强有力的技术解决方案。

Abstract:

The operation cost can be reduced effectively in open sea duing the ultra-deep water drilling. However， due to the influence of ultra-deep water and ultra-shallow （“double ultra” for short） environment， it faced with difficulties and challenges such as the swaying of cable logging instruments caused by shallow water surge， the difficulty of “entering hole” of cable testing instruments and the hidden safety problems of down-hole operation. In this case， the 20in casing is used to seal off the shallow surge to form an effective sealing. Making full use of the underwater robot to ensure the success of the instrument to “get into the hole”； The speed of the instrument is strictly controlled， and the dual monitoring mode of “ROV underwater + platform control panel” is adopted to ensure the safety of operation. A pilot test was made in several “double ultra” exploration wells in Qiongdongnan Basin， South China Sea， and several wireline logging operations were successfully carried out， detailed logging data were obtained， and operating costs were greatly reduced. This operation practice accumulated valuable experience for subsequent ultra-deep open sea operations， and provided a powerful technical solution for offshore oil and gas exploration and development to increase the reserves and production， reduce costs and increase efficiency.