塔里木盆地跃进地区奥陶系储层成因机理  

Genetic Mechanism of Ordovician Reservoirs in Yuejin Area,Tarim Basin

作　　者：刘存革 韩拥强 刘永立[3] 罗鹏[4] 罗明霞[3] LIU Cunge;HAN Yongqiang;LIU Yongli;LUO Peng;LUO Mingxia(College of Petroleum Engineering,Guangdong University of Petrochemical Technology,Maoming 525000,China;Xinjiang Bota Oilfield Technical Service Co.,Ltd.,Korla 841000,China;Exploration and Development Research Institute,Northwest Oilfield Company,Sinopec,Urumqi 830011,China;Sichuan Institute of Land Planning and Survey,Chengdu 610045,China)

机构地区：[1]广东石油化工学院石油工程学院,广东茂名525000 [2]新疆博塔油田技术服务有限公司,新疆库尔勒841000 [3]中国石化西北油田分公司勘探开发研究院,新疆乌鲁木齐830011 [4]四川省国土勘测规划研究院,四川成都610045

出　　处：《广东石油化工学院学报》2023年第3期1-6,共6页Journal of Guangdong University of Petrochemical Technology

基　　金：国家科技重大专项(2017ZX05005-002);广东石油化工学院科学研究基金(2017rc23)。

摘　　要：通过对岩芯、薄片的观察,结合扫描电镜、阴极发光、碳氧同位素、锶同位素和稀土元素的分析化验资料,探讨了塔里木盆地跃进地区中下奥陶统缝洞型储层的成因机理。沿裂缝断续分布的溶蚀孔洞、围岩和裂缝中的萤石交代产物表明存在热液溶蚀和交代作用,而基质晶间孔中的短柱状和柱状石英晶体、溶蚀孔洞方解石的低^(87 )Sr/^(86 )Sr比值(0.708407)、硅质结核的Eu正异常均表明存在岩浆期后的深部热液流体的溶蚀、交代和胶结作用。跃进地区中下奥陶统发育多期活动的走滑断裂带,由于基质低孔低渗,二叠纪晚期的岩浆期后热液流体主要沿断裂带进入中下奥陶统地层中进行溶蚀改造,随后的胶结作用对围岩中的孔隙网络造成严重的破坏,进一步增强了研究区内储层的非均质性。走滑断裂带控制着跃进地区中下奥陶统规模缝洞型储层的形成与分布,热液溶蚀作用进一步改善了缝洞型储层内部的渗流能力。This research focuses on the genetic mechanism of fracture-cave reservoirs in the Middle-Lower Ordovician in Yuejin area of Tarim Basin,through the observation of cores and thin sections,combined with the analysis and test data of scanning electron microscope,cathodoluminescence,carbon and oxygen isotopes,strontium isotopes and rare earth elements.The dissolution vugs intermittently distributed along the fractures,the fluorites metasomatic origin in the surrounding rocks and fractures indicate the existence of hydrothermal dissolution and metasomatism.However,the short columnar and columnar quartz crystals in the matrix inter-granular pores,the low ^(87 )Sr/^(86 )Sr ratio of calcite(0.708407)in the dissolution vugs and the Eu positive anomaly of siliceous nodules all indicate the dissolution,metasomatism and cementation of deep hydrothermal fluid after the magmatic period.Middle-Lower Ordovician in Yuejin area developed multi-stage active strike slip fault zones.Due to the low porosity and permeability of the matrix,the post magmatic hydrothermal fluid mainly entered Middle-Lower Ordovician strata along the fault zones for dissolution.The subsequent cementation caused serious damage to the pore networks in the surrounding rock and further enhanced the heterogeneity of reservoir in the study area.The strike slip fault zones controlling the formation and distribution of large-scale fracture-cave reservoirs in the Middle-Lower Ordovician in Yuejin area and hydrothermal dissolution further improve the seepage performance in the fracture-cave reservoirs.

关 键 词：热液溶蚀 走滑断层 中下奥陶统 塔里木盆地 

分 类 号：TE122[石油与天然气工程—油气勘探]