川西坳陷新场—新盛地区须二段致密砂岩气水富集特征及成因机制  

Gas-water enrichment characteristics and genetic mechanism of the second member of Xujiahe Formation tight sandstone in Xinchang-Xinsheng area of Western Sichuan Depression

作　　者：李莎 陈冬霞 王翘楚[1,2] 陈雨荷 刘雅利 岳大力[1,2] 屈林博 廖昌珍[3] Sha LI;Dongxia CHEN;Qiaochu WANG;Yuhe CHEN;Yali LIU;Dali YUE;Linbo QU;Changzhen LIAO(National Key Laboratory of Petroleum Resources and Engineering,Beijing 102249,China;College of Geosciences,China University of Petroleum,Beijing 102249,China;Petroleum Exploration and Production Research Institute,SINOPEC,Beijing 100083,China)

机构地区：[1]油气资源与工程全国重点实验室,北京102249 [2]中国石油大学(北京)地球科学学院,北京102249 [3]中国石化石油勘探开发研究院,北京100083

出　　处：《天然气地球科学》2024年第11期2012-2028,共17页Natural Gas Geoscience

基　　金：国家自然科学基金(编号:42302141);中国石油大学(北京)科研基金(编号:2462023XKBH001)联合资助。

摘　　要：川西坳陷须家河组致密气资源潜力大,但单井普遍产水是制约须二段气藏高效开发的重要因素。在对新场—新盛地区须二段致密气藏气水富集特征分析的基础上,结合铸体薄片、核磁共振、高压压汞等实验技术,阐明断缝及基质储层对气水富集的控制作用,揭示致密气藏气水的成因机制。结果表明:①研究区主要划分出5种气水关系类型,富气贫水型、含气贫水型气水类型主要分布于近南北向大规模断层附近,纵向上位于浅部上亚段;富气富水型、贫气富水型位于大规模四级断层附近,以中亚段较为集中;贫气贫水型远离断层,下亚段分布较多。②成藏期四级断层、高角度2期裂缝控制气水富集,基质储层的储层物性差异导致的强非均质性造成纵向气水分异,储层微观孔隙结构影响气水渗流及流体赋存进而控制局部气水分布。③受储层非均质性、断缝改造的宏观控制与储层孔隙结构的微观控制的耦合作用,划分5类断缝—砂体组合,其中,断缝区内—高角度裂缝—高孔渗强连通砂体组合最有利于气的富集,非断缝区—低孔渗差连通砂体不利于气水的发育。研究成果将对致密砂岩气藏勘探开发提供有利依据。The potential of tight gas resource of Xujiahe Formation in the Western Sichuan Depression is great,but the water productivity of an individual well is an important factor restricting the efficient development of the gas reservoir of the second member of Xujiahe Formation(Xu 2 Member,Tx_(2)).Based on the analysis of the gas and water enrichment characteristics of the Xu 2 Member tight gas reservoir in the Xinchang-Xinsheng area,combined with experimental techniques such as cast thin sections,nuclear magnetic resonance,and high-pressure mercury intrusion,it was clarified that fractures and matrix reservoirs have important effects on gas and water enrichment.The controlling effect of gas accumulation can reveal the formation mechanism of gas and water in tight gas reservoirs.The results showed that:(1)There are five types of gas-water relationship in the study area,which are rich gas-rich water type,rich gas-poor water type,little gas-poor water type,poor gas-rich water type and poor gas-poor water type.The rich gas-rich water type and little gas-poor water type gas-water relations are mainly distributed in the upper shallow sub-member of the Tx_(2) along with the large-scale faults.The rich gas-rich water type and poor gas-rich water type gas-water relations are distributed in the middle sub-member near the fourth-grade faults which were widely developed in the study area.The poor gas-poor water type gas-water relations were mainly distributed in the lower sub-member and far away from the developed faults.(2)The fourth-grade faults which were active in the hydrocarbon charging periods and the two-period fractures in high degree are dominant for the accumulation of the gas and water.Furthermore,the heterogeneity disparity of the sandstone reservoir led by the disparity of the reservoir physical properties caused the differentiation between the gas and water in the lateral.The microscopic pore structures of the tight sandstone reservoirs had influences on the gas-water interaction and seepage and hence the partial g

关 键 词：致密气藏 川西坳陷 气水富集特征 须家河组 成因机制 

分 类 号：TE122.1[石油与天然气工程—油气勘探]