旅大25-1区块深层复杂结构井异常压力下潜山钻井技术创新及其应用

Innovation and Application of Buried Hill Drilling Technology for Deep Complex Structure Wells under Abnormal Pressure in Lvda25-1 Block

旅大25-1区块火成岩钻遇异常压力,打破了传统的潜山是正常压力体系的认识,该区块仅在1976—2001年钻探了秦皇岛30-1构造的4口井,其主要目的层中生界是渤海油田勘探新层系,同时井位又位于限制区域,安全风险高、作业难度大。基于前人的认识,结合旅大25-1区块实际情况,通过对随钻压力双监测技术、井场精细调控钻井技术、异常压力有效封隔技术的攻关,最终形成了一套异常压力条件下潜山钻井关键技术。通过实际应用证明该技术具有良好的推广价值。

The abnormal pressure was encountered in igneous rock drilling in Lvda25-1 block,which breaks the traditional understand⁃ing that buried hill is a normal pressure system.Only four wells in Qinhuangdao 30-1 structure were drilled in this block from 1976 to 2001.The main target layer is Mesozoic,which is a new exploration layer series in Bohai oilfield.At the same time,the wells are locat⁃ed in a restricted area,so the safety risk is high and the operation is difficult.During the operation of exploration well A,there was a complex situation of upper overflow and lower leakage,without realizing exploration purpose and sidetracking exploration well B.Based on the previous understanding and the actual situation of Lvda 25-1 block,through the development and application of pressure while drilling dual monitoring technology,well site fine-control drilling technology and abnormal pressure effective sealing technology,a set of key technologies for buried hill drilling under abnormal pressure conditions are finally formed.The practical application shows that this set of technologies has good promotion value.