鲁克沁北一区二叠系梧桐沟组储层特征及其对注水开发的影响

THE RESERVOIR CHARACTERISTICS AND THE INFLUENCE TO WATERFLOOD DEVELOPMENT OF PERMIAN WUTONGGOU FORMATION IN BLOCK BEIYI, LUKEQIN OILFIELD

通过常规薄片、铸体薄片、扫描电镜、压汞、岩心常规分析等资料,对北一区梧桐沟组储层岩石学、储层孔隙类型、孔隙结构、粘土矿物及物性特征进行研究,并简要分析了其对注水开发的影响。研究表明,梧桐沟组三个砂组岩性均为岩屑砂岩,储集空间以剩余粒间孔为主,孔隙结构分为三类,从物性来看,1砂组属于中低孔低渗储层,3砂组属于低孔特低渗储层。1砂组的储集性能和物性均好于3砂组,且1砂组砂体延伸更远,向北扩展潜力很大。此外,研究区注水试验存在欠注问题,分析认为这与储层物性、孔隙结构以及粘土矿物类型和含量有关,这将为该区注水开发对策提供依据。

Based on conventional thin sections, casting thin sections, scanning electron microscope, mercury injection and core analysis, the reservoir petrologic characteristics, pore types, pore structure, clay minerals and physical property characteristics of Wutonggou formation have been studied. The influence to waterflood development has been analyzed as well. The studies indicate that the lithology of three sand bodies of Wutonggou formation is lithic sandstone, the residual intergranular pore is the main type, and the pore structure is divided into three types. The physical property of first sand body is middle-low porosity and low permeability,and the third is low porosity and ultra-low permeability. The physical property of first sand body is better than that of the thirds, but the sand of first sand body extends farther. Besides, the problem of insufficient water injection exists in study area. It is related to physical property, pore structure and types and content of clay minerals. These conclusions will provide basis for waterflood development.