玛西斜坡区百口泉组二段储层特征及物性控制因素

Reservoir Characteristics and Controlling Factors of Physical Property in Second Member of Baikouquan Formation in Western Slope of Mahu Sag

玛西斜坡区紧邻玛湖凹陷,区内百口泉组二段的油气勘探潜力巨大,对储层特征及物性控制因素进行分析是百口泉组二段油气进一步勘探开发的关键。通过岩心观察、相关岩石薄片分析(普通、荧光以及铸体)、扫描电镜、物性以及试油等资料,对百口泉组二段不同沉积环境内砂砾岩储层岩石学特征、储集物性、孔隙结构以及储集空间进行详细分析,总结储层物性的控制因素。结果表明:研究区百口泉组二段岩石类型以砂砾岩为主;储集层属于特低孔-低渗类,含油性同物性成正相关关系;储集空间包括原生粒间孔、次生孔隙和微裂缝。沉积微相对有利储层分布和储集质量有较大的影响,成岩作用中压实作用是储集物性较差的根本因素,胶结物以及沉积组分为后期溶蚀作用提供物质基础;古地貌控制有利储层平面展布,异常压力和微裂缝有利于储集物性的改善。研究成果对百口泉组二段勘探开发具有重要的指导意义。

Maxi slope area nears Mahu Sag, where second member of Baikouquan Formation had great oil and gas exploration potential, and it is the key factor for deeper exploration and development to search reservoir characteristics and controlling factors of physical property. Through core observation, many rock slices analysis, SEM, physical property and oil testing data, petrology character, physical property, pore structures and reserve spaces in sand-conglomerate reservoirs of different sedimentary environment in second member of Baikouquan Formation were detailed searched, and generalized controlling factors on physical property of reservoirs for exploiting potentialities. The results shows that rock types in second member of Baikouquan formation in the study area are conglomerate, and the reservoir belongs to ultra-low porosity and low permeability, and there is a positive correlation between the oil-bearing property and the physical property. The reservoir spaces comprise of primary intergranular pores, secondary pores and micro fractures.Sedimentary micro-facies has a large affection on favorable reservoir distribution of favorable reservoir and reservoir quality.Compaction is the basic factor of low reservoir physical property in diagenesis.Cement and sedimentary components provide material basis for later dissolution.The paleogeomorphology control is favorable for the plane distribution of reservoirs, and the abnormal pressure and micro fractures are helpful to the improvement of reservoir physical properties.These research results have certain influence on the exploration and development of second member of Baikouquan Formation.