摘要
库车凹陷储层埋藏深,压力系统异常,盐膏层发育,钻井周期长,井下复杂情况较多。复杂地层X-射线衍射分析结果表明,吉迪克组、苏维依组和巴什基奇克组发育膏层并含有方解石,黏土矿物以伊利石和绿泥石为主。扫描电镜分析表明,岩石较致密,颗粒充填片状泥质,微孔隙不同程度发育。对于盐膏层较发育的吉迪克组和苏维依组,钻井液应以盐水基钻井液为主并以适宜的钻井液密度来应对盐膏层的蠕变和溶解;对于舒善河组具有一定活性泥岩应提高钻井液抑制性并采用适宜的密度以稳定井壁。由于该区存在多压力系统,应保持高密度条件下钻井液具有较好的流变性。
Reservoirs in Kuqa Depression was buried deeply,where there existed pressure abnormal and anhydrite development,drilling interval was long,downhole situation was complex.X-ray diffraction analysis of complex formation indicated that in Jidike,Suweiyi and Bashijiqike Formations anhydrite was developed and calcite was contained in it,clay minerals were mainly of illite and chlorite.SEM analysis shows that the lithologh was tight,shale was in lamellate filling,and the micro pore was developed in various degrees.In Jidike and Suweiyi Formations,a salt-based drilling fluid should be mainly used and suitable drilling fluid density should be deployed in the situation of creeping and dissolution.For the mudstone with certain activity in Shushanhe Formation,drilling inhibition and suitable density should be used to stabilize the wellbore.Because in the area there exists a multi-pressure system,good rheology should be maintained under high density condition.
出处
《石油天然气学报》
CAS
CSCD
2013年第10期134-137,9,共4页
Journal of Oil and Gas Technology
基金
国家科技重大专项(2011ZX05049-02-02)
关键词
库车山前构造
复杂地层
理化性能
井壁稳定
钻井液
Kuqapiedmont structure
complex formation
physical and chemical property
borehole stability
drilling fluid
