莺歌海域某区块安全钻井液密度窗口计算分析  

Calculation and analysis of safety drilling fluid density window in a block in Yingge Sea

作　　者：李华洋 吴惠梅[1] 朱施杰 LI Huayang;WU Huimei;ZHUShijie(College of Petroleum Engineering,Yangtze University,Wuhan 430100,China;State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Science,Wuhan 430071,China;College of Resources and Safety,Chongqing University,Chongqing 400044,China)

机构地区：[1]长江大学石油工程学院,湖北武汉430100 [2]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉430071 [3]重庆大学资源与安全学院,重庆400044

出　　处：《能源化工》2020年第2期54-57,共4页Energy Chemical Industry

基　　金：国家自然科学基金项目(51774050);2018年湖北省大学生创新创业训练计划(2018319);中国科学院大学生创新实践训练计划(20194000120)。

摘　　要：针对莺琼盆地前期已钻深水井及高温高压井复杂情况较多,特别是由于压力窗口窄导致的溢流、压井过程中井漏复杂情况率高等问题,结合其复杂的海洋地质环境,建立了一套切合深水条件的地层压力计算模型。以X-1井区为例,采取了适用于由欠压实作用引起的异常高压区域的伊顿法预测孔隙压力,对于坍塌压力则依据双重有效应力理论建立了考虑地层渗透条件的计算模型,最后基于应力强度因子理论,构建了与深水钻井的破裂环境相吻合的坍塌压力预测模型。根据上述模型确定了X-1井的安全钻井液密度窗口,经与临井实测点比对,压力预测精度达到95%以上,为钻井方案的设计和钻井液密度的选取提供了科学依据。Aiming at the complex problems of deepwater wells and high-temperature and high-pressure wells that have been drilled in the early stage of the Yingqiong Basin,especially the problems caused by the narrow pressure window and the high rate of leakage in the well killing process,combined with its complex marine geological environment,a set of formation pressure calculation models suitable for deep water conditions is established.Taking the X-1 well area as an example,the Eaton method is applied to predict the pore pressure in the area of abnormal high pressure caused by under-compaction.For the collapse pressure,a calculation model considering formation permeability conditions is established based on the double effective stress theory.Based on the stress intensity factor theory,a slump pressure prediction model consistent with the fracture environment of deepwater drilling is constructed.According to the above model,the safe drilling fluid density window of well X-1 is determined,and the accuracy of pressure prediction reaches 95%by comparison with the actual measured points of the adjacent wells,which provide a scientific basis for the design of the drilling scheme and the selection of drilling fluid density.

关 键 词：深水钻井孔隙压力 破裂压力 坍塌压力 密度窗口 

分 类 号：TE254[石油与天然气工程—油气井工程]