基于录井参数不确定性的随钻地层压力分析预测  

Analysis and prediction of formation pressure while drilling based on uncertainties of mud logging parameters

作　　者：徐婕 姜维寨 牛华夏 杨学辛 戴广阔 杨清纯 XU Jie;JIANG Weizhai;NIU Huaxia;YANG Xuexin;DAI Guangkuo;YANG Qingchun(No.2 Mud Logging Company,BHDC,CNPC,Renqiu,Hebei 062552,China)

机构地区：[1]中国石油渤海钻探第二录井公司

出　　处：《录井工程》2023年第3期7-14,共8页Mud Logging Engineering

基　　金：中国石油渤海钻探工程公司揭榜挂帅重大研发项目“油气井工程地质一体化深度融合系统开发”(编号:2022ZD01F)。

摘　　要：在同一岩性地层中,由于钻速、转盘转速、钻压、钻井液密度和岩石密度等录井参数存在不确定性,导致基于录井参数的随钻地层压力预测存在一定的不确定性。针对该问题,分析了钻速、转盘转速、钻压、钻井液密度和岩石密度等录井参数的不确定性特征,进而采用改进的Rosenbluthe方法推导得出dc指数、上覆地层垂向应力及随钻地层压力的不确定性分析表达式,同时提出了基于录井参数的随钻地层压力不确定性分析方法,最后得到了地层压力的概率分布。以某区块HT 101井为例,分别应用不确定性分析方法和蒙特卡罗方法对地层压力的概率分布进行预测,结果表明,不确定性分析方法与蒙特卡罗方法的压力预测一致性达95%以上,其压力预测精度能够满足工程需要。In the strata of the same lithology,due to the uncertainties of mud logging parameters such as drilling speed,rotary speed,weight on bit,drilling fluid density and rock density,some uncertainties exist in predicting formation pressure while drilling based on mud logging parameters.To solve this problem,the uncertainty characteristics of mud logging parameters including drilling speed,rotary speed,weight on bit,drilling fluid density and rock density were analyzed.Then,the analytical expressions of uncertainties in dc index,vertical stress of overlying strata and formation pressure while drilling were derived by using the improved Rosenbluthe method.At the same time,a method for analyzing the uncertainties of formation pressure while drilling based on mud logging parameters was proposed,and the probability distribution of formation pressure was finally obtained.Taking well HT 101 in a block as an example,uncertainty analysis method and Monte Carlo method were used to predict the probability distribution of formation pressure respectively.The results showed that the consistency of pressure prediction between uncertainty analysis method and Monte Carlo method was more than 95%,and the accuracy of pressure prediction can meet the engineering needs.

关 键 词：随钻地层压力 录井参数 不确定性 Rosenbluthe方法 概率分布 蒙特卡罗方法 

分 类 号：TE132.1[石油与天然气工程—油气勘探]