Abstract:

In recent years,more than 30% of newly discovered offshore oil and gas structures have been found in deep layers,making deep oil and gas an important resources for future energy supply growth.China National Offshore Oil Corporation (CNOOC) has achieved technological breakthroughs in the Bohai region,which serves as the main field for deep oil and gas reservoir.A series of key technologies have been developed,including accurate prediction and monitoring of formation pressure,quantitative evaluation of fractured leakage,multi-field coupled wellbore stability analysis,ROP optimization in deep hard rock drilling and protection of fractured reservoirs,enabling efficient exploration and development of oil and gas resources in the Bohai region at depths ranging from 5,000 meters to 5,500 meters,thus meeting the requirements of deep oil and gas drilling.Based on these key technologies,a series of deep oil and gas fields such as BZ19-6 condensate gas field,BZ13-2 deep oil field,and BZ26-6 100-million-tonne buried hill oil field have been successfully drilled and discovered in the Bohai Sea.The drilling time decreased from the initial 140 days to less than 40 days with a record-setting operation time of only 31 days for a 5,100-meter well,building a strong foundation for further exploration and development of deep oil and gas reserves in the Bohai Sea.

Key words: deep oil and gas, ROP optimization, fractured reservoir, reservoir protection

摘要：

近年来海上新发现的含油气构造超过30%来自于深层,深层油气已成为未来油气增长的重要接替领域。中国海油针对作为深层油气主战场的渤海区域进行了技术攻关,形成了地层压力精准预测与监测、裂缝性漏失量化评估、多场耦合井眼稳定性分析、深层硬岩钻井提速、裂缝性储层保护等系列关键技术,实现了渤海区域5 000~5 500 m埋深油气资源的高效勘探与开发,阶段满足了深层油气的钻探需求。依托研究形成的系列关键技术,渤海区域相继成功钻探并发现了BZ19-6大型凝析气田、BZ13-2深层油田、BZ26-6亿吨级隐蔽型潜山油田等系列深层油气田,钻井周期由最初的140 d下降至不到40 d,并创造了5 100 m深井最短31 d建井记录,为渤海深层油气勘探开发奠定了良好的基础。

关键词: 深层油气, 钻井提速, 裂缝性储层, 储层保护