胜北洼陷三间房组致密储集层成岩作用及孔隙演化  

Diagenesis and Pore Evolution of Tight Reservoirs of Sanjianfang Formation in Shengbei Subsag

作　　者：周港 程甜 李杰[4] 陈安清[1,2] 李富祥 徐慧 徐胜林[1,2] ZHOU Gang;CHENG Tian;LI Jie;CHEN Anqing;LI Fuxiang;XU Hui;XU Shenglin(Chengdu University of Technology,State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu,Sichuan 610059,China;Chengdu University of Technology,Institute of Sedimentary Geology,Chengdu,Sichuan 610059,China;PetroChina Tuha Oilfield Company,Development Department,Hami,Xinjiang 839009,China;PetroChina Tuha Oilfield Company,Research Institute of Exploration and Development,Hami,Xinjiang 839009,China)

机构地区：[1]成都理工大学油气藏地质及开发工程国家重点实验室,成都610059 [2]成都理工大学沉积地质研究院,成都610059 [3]中国石油吐哈油田分公司开发事业部,新疆哈密839009 [4]中国石油吐哈油田分公司勘探开发研究院,新疆哈密839009

出　　处：《新疆石油地质》2023年第3期289-298,共10页Xinjiang Petroleum Geology

基　　金：国家自然科学基金(41872109)。

摘　　要：吐哈盆地台北凹陷胜北洼陷中侏罗统三间房组油气资源丰富,但该组储集砂体致密,非均质性较强,制约了油气的勘探开发。以胜北洼陷中侏统三间房组砂岩储集层为研究对象,在岩心观察的基础上,结合薄片观察、电镜扫描、高压压汞测试等,研究致密砂岩储集层成岩作用和孔隙演化规律。结果表明,胜北洼陷三间房组储集层以长石岩屑砂岩为主,其次为岩屑砂岩,孔隙类型以次生孔隙为主,平均孔隙度为6.44%,平均渗透率为0.18 mD,属于低孔低渗储集层;成岩演化过程为压实—自生黏土矿物胶结、绿泥石环边胶结—石英Ⅰ期次生加大、长石溶解—钠长石化—绿泥石环边胶结—碳酸盐岩胶结—长石溶解—高岭石伊利石化,目前处于中成岩阶段B期。胜北洼陷三间房组储集砂岩平均初始孔隙度为34.66%,早成岩阶段A期压实作用平均减孔14.05%,胶结作用平均减孔0.50%;早成岩阶段B期压实作用平均减孔3.21%,胶结作用平均减孔0.75%;中成岩阶段A期压实作用平均减孔7.02%,胶结作用平均减孔4.26%;中成岩阶段B期压实作用平均减孔1.08%,胶结作用平均减孔0.75%。中成岩阶段A期溶蚀作用是研究区增孔的关键,平均增孔量为3.38%。The Sanjianfang formation in the Shengbei subsag of the Tabei sag in the Turpan-Hami basin is rich in oil and gas resources.However,the sandstone reservoirs in this formation are tight and heterogeneous,which hinders the exploration and development of oil and gas.Based on core and thin-section observations,electron microscopy scanning,and high-pressure mercury injection tests,the diagenetic processes and pore evolution of the tight sandstone reservoirs of the Middle Jurassic Sanjianfang formation in the Shengbei subsag were studied.The results show that the tight sandstone reservoirs of the Sanjianfang formation are mainly composed of feldspathic litharenite and lithic sandstone,and dominantly contain secondary pores,with an average porosity of 6.44%and an average permeability of 0.18 mD,indi-cating low-porosity and low-permeability reservoirs.The diagenetic evolution process includes compaction-authigenic clay mineral cemen-tation,chlorite-rimming cementation-phase-Ⅰquartz enlargement and feldspar dissolution-albitization-rimmed chlorite cementation-car-bonate cementation-feldspar dissolution-kaolinite illitization.The sandstone is currently in phase B of the middle diagenetic stage.The av-erage initial porosity of the Sanjianfang formation sandstones is 34.66%.The average reduction in porosity is 14.05%due to compaction and 0.50%due to the cementation in phase A of the early diagenetic stage,3.21%due to compaction and 0.75%due to cementation in phase B of the early diagenetic stage,7.02%due to compaction and 4.26%due to cementation in phase A of the middle diagenetic stage,and 1.08%due to compaction and 0.75%due to cementation in phase B of the middle diagenetic stage.The dissolution process in phase A of the middle diagenetic stage is crucial to the increase in porosity,with an average increase of 3.38%.

关 键 词：吐哈盆地 台北凹陷 胜北洼陷 三间房组 中侏罗统 致密储集层 成岩作用 孔隙演化 

分 类 号：TE122.2[石油与天然气工程—油气勘探]