塔里木盆地中下寒武统膏质白云岩盖层突破压力预测方法  

Prediction method for breakthrough pressure capability of gypsum dolomite caprock of Middle and Lower Cambrian in Tarim Basin

作　　者：史集建[1,2] 张璐 林潼[3] 于北溟[4] SHI Jijian;ZHANG Lu;LIN Tong;YU Beiming(School of Earth Sciences,Northeast Petroleum University,Daqing 163318,China;Key Laboratory of Natural Gas Sealing Mechanism,CNPC Key Laboratory of Gas Reservoir Formation and Development,Daqing 163318,China;PetroChina Research Institute of Petroleum Exploration&Development,Beijing 100083,China;Exploration and Development Research Institute of PetroChina Daqing Oilfield Co.,Ltd.,Daqing 163712,China)

机构地区：[1]东北石油大学地球科学学院,黑龙江大庆163318 [2]中国石油天然气集团有限公司天然气成藏与开发重点实验室天然气封盖机理重点研究室,黑龙江大庆163318 [3]中国石油勘探开发研究院,北京100083 [4]中国石油大庆油田有限责任公司勘探开发研究院,黑龙江大庆163712

出　　处：《大庆石油地质与开发》2024年第5期22-31,共10页Petroleum Geology & Oilfield Development in Daqing

基　　金：国家自然科学基金项目“高温高压条件下泥页岩润湿性表征实验研究”(41702153);油气资源与探测国家重点实验室开放课题“泥岩盖层内油润湿运移路径形成机理研究”(WX20160081)。

摘　　要：针对塔里木盆地中下寒武统白云岩盖层层段不易精确厘定和物性变化复杂的问题,在运用岩性统计分析和实验测试手段的基础上,以优势盖层岩性膏质白云岩为主要研究对象,确定其具有不同物性特征的分散状、斑块状、裂缝分散状、裂缝斑块状4种微观结构,进而得到颗粒结构、石膏-黏土含量和裂缝发育程度是影响白云岩突破压力的3个主要因素。据此选取能够响应膏质白云岩岩性和物性特征的测井曲线,运用逐步线性回归分析,明确膏质白云岩突破压力与自然伽马和补偿中子测井数据相关性最强,进而构建其突破压力的预测公式。应用该方法可以准确地预测塔里木盆地中下寒武统膏质白云岩的突破压力,并通过单井分析和连井剖面初步确定巴楚-塔中隆起地区中下寒武统盖层发育特征为“横向上彼此相连,纵向上互相叠置”,对其下部储层内的油气封闭起着积极作用。研究结果与目前油气发现部位具有良好的一致性,可以为塔里木盆地中下寒武统天然气保存条件分析及明确下一步勘探层位提供指导。Aiming at the challenge of determining caprock interval accurately and the complex property variation of Middle and Lower Cambrian dolomite in Tarim Basin,based on lithologic statistical analysis and experimental testing method,gypsum dolomite which is dominant lithology of caprock is taken as main research object,and is determined as 4 types with different microstructures including dispersed,patched,fractures dispersed and fractures patched structures,thus getting 3 main factors of grain structure,gypsum-clay content and fractures development af-fecting the brdakthrough pressure of gypsum dolomite.Accordingly,by selecting logging curves which can respond lithology and property of gypsum dolomite,it is determined that breakthrough pressure of gypsum dolomite has the strongest correlation with natural gamma ray and compensated neutron logging data by stepwise regression analysis,thus prediction formula for breakthrough pressure of gypsum dolomite is established.This method can be used to ac-curately analyze breakthrough pressure of Middle and Lower Cambrian gypsum dolomite in Tarim Basin,and single well analysis and well tie section preliminarily determine that the development characteristics of Middle and Lower Cambrian caprock in Bachu-Tazhong Uplift area are“horizontally connected to each other,and vertically stacked with each other”,which plays positive role in oil and gas sealing in the lower reservoir.The research results have good consistehcy with current oil and gas discovery and provide guidance for analysis of natural gas preservation conditions and determination of next exploration interval of Middle and Lower Cambrian in Tarim Basin.

关 键 词：膏质白云岩 盖层 突破压力 塔里木盆地 中下寒武统 多元统计分析 

分 类 号：TE122.2[石油与天然气工程—油气勘探]