成岩演化对陆相致密砂岩储层可动性差异的控制机理及演化模式——以松辽盆地北部下白垩统扶余油层为例  

The control mechanism and evolution model of diagenesis on the mobility difference of continental tight sandstone reservoirs:Taking Fuyu oil layer of Lower Cretaceous in the northern Songliao Basin as an example

作　　者：邵鑫笛 宋岩[1,2] 姜振学[1,2] 姜林[3] 马行陟[3] 张原豪 SHAO Xindi;SONG Yan;JIANG Zhenxue;JIANG Lin;MA Xingzhi;ZHANG Yuanhao(State Key Laboratory of Petroleum Resources and Engineering,China University of Petroleum-Beijing,Beijing 102249,China;Unconventional Petroleum Research Institute,China University of Petroleum-Beijing,Beijing 102249,China;Research Institute of Petroleum Exploration and Development,PetroChina,Beijing 100083,China)

机构地区：[1]中国石油大学(北京)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)非常规油气科学技术研究院,北京102249 [3]中国石油勘探开发研究院,北京100083

出　　处：《石油科学通报》2025年第1期16-34,共19页Petroleum Science Bulletin

基　　金：中石油“前瞻性、基础性”课题“全油气系统理论与非常规油气成藏机理”(2021DJ0101)资助。

摘　　要：可动性是致密砂岩在油气开发、预测以及评价过程中的重要参数。致密砂岩经历的成岩作用复杂多样,成岩演化过程对可动性的控制机理不明确,制约了致密砂岩油气成藏机理研究以及甜点优选工作。本研究以松辽盆地北部泉头组扶余油层致密砂岩为研究对象,通过高压压汞、核磁共振、扫描电镜以及薄片观察等手段,探究成岩演化过程中成岩作用对致密砂岩可动性的约束机理。研究表明,早成岩阶段主要发生压实作用,孔隙类型主要为原生孔隙和残余粒间孔,主要发育宏孔和介孔,宏孔是可动流体的主要赋存空间,可动流体饱和度较高;中成岩阶段A期主要发生压实作用和溶蚀作用,同时发生一定程度的胶结作用,孔隙类型主要为残余粒间孔和溶蚀孔,孔隙结构逐渐复杂且连通性降低,介孔占比逐渐增加,可动流体饱和度持续下降;中成岩阶段B期主要发生胶结作用,大量胶结物的沉淀占据了残余粒间孔以及溶蚀孔等有效储集空间和喉道,宏孔基本消亡,介孔成为流体主要的赋存空间,可动性较差。不同成岩阶段发生的成岩作用对储层孔隙结构的控制作用决定了致密砂岩储层的可动性。最后建立了成岩演化约束下的致密砂岩储层可动性演化模式,阐明了成岩演化、孔隙结构以及可动流体赋存之间的潜在关系,对更好认识致密砂岩储层甜点的空间分布规律和可动性差异,同时可为开发手段技术方案的进一步优化提供概念依据。Mobility is an important parameter of tight sandstone in the process of oil and gas development,prediction,and evaluation.The complex diagenesis process and the lack of knowledge about the control mechanism of the evolution process on mobility restrict the understanding of the hydrocarbon accumulation mechanism and"sweet spot"optimization of tight sandstone.In this study,the tight sandstone of the Fuyu oil layer of the Quantou Formation in the northern Songliao Basin was taken as the research object.Utilizing a combination of high-pressure mercury injection,nuclear magnetic resonance,scanning electron microscopy,and thin section observation,the mechanism of diagenesis on the mobility of tight sandstone in the diagenetic evolution process was explored.The results show that compaction mainly occurs in the early diagenesis stage.The pore types are mainly primary pores and residual intergranular pores.Macropores and mesopores are mainly developed.Macropores are the main occurrence space of movable fluid,and the saturation of movable fluid is high.In the middle diagenesis stage A,compaction and dissolution mainly occur,and a certain degree of cementation occurs at the same time.The pore types are mainly residual intergranular pores and dissolution pores.The pore structure is gradually complicated and the connectivity is reduced.The proportion of mesopores gradually increases,and the saturation of movable fluid continues to decrease.In the B stage of the middle diagenetic stage,cementation mainly occurred.The precipitation of many cements occupied the effective reservoir space and throats such as residual intergranular pores and dissolution pores.The macropores almost disappeared,and the mesopores became the main occurrence space of the fluid,and the mobility was poor.The control of diagenesis on reservoir pore structure in different diagenesis stages determines the mobility of tight sandstone reservoirs.Finally,the mobility evolution model of the tight sandstone reservoirs under the constraint of diagenetic evolution

关 键 词：可动性 孔隙结构 成岩作用 致密砂岩 扶余油层 松辽盆地 

分 类 号：P618.13[天文地球—矿床学] TE122[天文地球—地质学]