摘要
通过岩芯、砂岩薄片、扫描电镜和物性、X衍射等综合分析,系统剖析徐家围子断陷沙河子组致密砂砾岩储层成岩相特征及成因。结果表明,沙河子组发育泥质杂基充填相、长石岩屑溶蚀相、石英次生加大相、绿泥石环边胶结相和碳酸盐胶结相等5种成岩相;由沉积作用形成的碎屑矿物组分、结构差异决定了各成岩相初始孔隙度,各成岩相中成岩作用类型和强度差异导致其孔隙演化路径各不相同,造成平面上宏观物性和微观孔隙结构的差异性分布。辫状河三角洲前缘沉积中长石岩屑溶蚀相和扇三角洲前缘沉积中绿泥石环边胶结相在天然气充注前仍具有较高的物性,是研究区致密砂砾岩最有利的成岩相带;泥质杂基充填相、碳酸盐胶结相和石英次生加大相在天然气充注前已完成致密化过程,不利于天然气聚集成藏。
In order to make clear the characteristic and genesis of tight sandstone diagenetic facies in Shahezi Formation,the core,thin-section,SEM,physical properties and X-ray analysis have been combined and systematically studied in Xujiaweizi Fault Depression.The result is that there are five kinds of diagenetic facies such as muddy-filling diagenetic facies,feldspardebris dissolution diagenetic facies,quartz overgrowth diagenetic facies,chlorite cementation diagenetic facies and carbon cementation diagenetic facies.The difference of mineral constituent and texture between different diagenesis facies which is controlled by sedimentation is the origin of porosity evolution,the type of main diagenesis and its intensity determine the porosity evolution path in different diagenetic facies and result in spatial differentiation of properties in macroscopic and pore structure in microscopic.Even though diagenesis destroy a lot of primary pore in feldspar-debris dissolution diagenetic facies in braided delta front and chlorite cementation diagenetic facies in fan delta front,they still retain a high property before gas injection in stage B of middle diagenesis phase,which make them a favorable reservoir for gas accumulation.The reservoir in muddy-filling diagenetic facies,carbon cementation diagenetic facies and quartz overgrowth have loss most of primary pore and complete the densification process before organic matters get matured,which make it dificult for gas inj ection and accumulation.
作者
冉清昌
钟安宁
周翔
王超
杨丹丹
RAN Qingchang;ZHONG Anning;ZHOU Xiang;WANG Chao;YANG Dandan(Exploration and Production Research Institute,Daqing Oilfield,CNPC,Daqing,Heilongjiang 163712,China;Great Wall Drilling Company,CNPC,Panjin,Liaoning 124010,China;Downhole Operation Branch Company,Daqing Oilfield,CNPC,Daqing,Heilongjiang 163716,China)
出处
《西南石油大学学报（自然科学版）》
CAS
CSCD
北大核心
2022年第1期13-26,共14页
Journal of Southwest Petroleum University(Science & Technology Edition)
基金
国家重大科技专项(2016ZX05001-002)
中国石油天然气股份有限公司重大科技专项(2016E-01)。
关键词
成岩相
致密砂岩
孔隙演化
沙河子组
徐家围子断陷
diagenetic facies
tight sandstone
porosity evolution
Shahezi Formation
Xujiaweizi Falut Depression
