玛湖凹陷夏子街地区三叠系百口泉组砂砾岩储层特征及控制因素

针对准噶尔盆地玛湖凹陷夏子街地区百口泉组砂砾岩储层，通过岩芯观察、薄片鉴定、阴极发光及定量统计分析等，对研究区岩石学特征、储集物性、成岩作用特征及差异性表征、储层控制因素进行了详细的研究。结果表明:研究区可识别出扇三角洲平原和扇三角洲前缘两个亚相类型。并总结出杂基支撑中砾岩相、杂基支撑细砾岩相、颗粒支撑中砾岩相、颗粒支撑细砾岩相、砾质砂岩相、含砾砂岩相、粗砂岩相、中砂岩相、细砂岩相、粉砂岩相及泥岩相11种岩相类型以及6种岩相组合类型。储集空间主要为长石、岩屑颗粒及杂基溶蚀形成的次生孔隙，孔隙度主要分布在2.5%~21.2%，平均7.94%，渗透率主要分布在（0.01~982）×10-3 μm2，平均为5.6×10-3 μm2，属于低孔低渗储层。研究区发育压实、胶结、溶解等成岩作用类型，共划分出8种成岩相。岩相和成岩相共同控制储层物性。扇三角洲平原泥石流沉积储层以杂基支撑中砾岩、杂基支撑细砾岩、中砂岩相和细砂岩相为主，压实作用强，杂基含量高，胶结作用与溶蚀作用弱，储集性能差，扇三角洲前缘分流河道储层以颗粒支撑中砾岩、颗粒支撑细砾岩、含砾砂岩和粉砂岩相为主，成岩作用复杂，相序底部压实较强，中部可见沸石与碳酸盐胶结，保留少量的原生粒间孔隙，并且不稳定岩屑颗粒和沸石胶结物通常发生溶解，形成次生孔隙，改善储层物性。

The Characteristics and Controlling Factors of Glutenite Reservoir in the Triassic Baikouquan Formation,Xiazijie Area,Mahu Depression

A detailed study of the sandy conglomerate reservoir in the Xiazijie, Baikouquan Formation, Mahu Depression,Junggar Basin,included the observation of cores,thin sections,X-ray tomography (XRT),cathodoluminescence (CL)analysis and quantitative statistical analysis,to assess the reservoir petrology,properties,diagenesis and control factors. The main lithology in the study area is glutenite,with fan delta plain and fan delta front subfacies. These were classified into eleven lithofacies types:matrix-supporting medium and fine conglomerate; particle-supporting medium and fine conglomerate;calcareous sandstone;gravel-bearing sandstone;coarse,medium and fine sandstone;siltstone;and mudstone,along with six combined facies types vertically. The main storage space is secondary porosity, consisting of dissolution pores in feldspars, debris and matrix. The reservoir in the study area has low porosity (2.5% 21.2%,average 7.94%)and low permeability (0.01×10-3 982×10-3 μm2,average 5.6×10-3 μm2). It was found that compaction, cementation and dissolution have led to eight types of diagenetic facies which, when combined with the lithofacies, controlled reservoir development. The debris flow reservoir of the fan delta plain mainly developed matrix-supporting medium-to-fine conglomerate facies and medium-to-fine sandstone facies. The high matrix content and strong compaction, together with weak cementation and dissolution in the reservoir, indicate poor storage capability. The underwater channel reservoir of the fan delta front mainly developed matrix-supporting medium-to-fine conglomerate facies,gravel-bearing sandstone facies and fine sandstones facies. The diagenesis in this reservoir is complex. The bottom of the phase sequence is generally strongly compacted;the central zones are cemented with zeolite and carbonates,in which a small number of primary intergranular pores have been retained. Unstabilized rock fragments and dissolved zeolite cements form secondary pore space and improve the physical properties of the reservoir.