盘古梁-周家湾地区三叠系延长组长6储层特征及影响因素分析

Analysis of Characteristics and Influential Factors of Chang-6 Reservoirs of Triassic Yanchang Formation in Panguliang-Zhoujiawan Area

鄂尔多斯盆地盘古梁-周家湾地区三叠系延长组长6是主要的产油层系，通过对该区主力油层的沉积岩石学特征、储层类型和孔隙结构及物性特征的研究，分析了影响储层的主要因素。本区储层岩性为长石细粒砂岩，少数为细粒岩屑长石砂岩，岩石矿物成熟度较低，结构成熟度较高，分选较好。经历了压实作用、胶结作用和溶解作用，孔隙类型以残余粒间孔隙和溶蚀孔为主，储层总体表现为低孔、低渗特征，局部存在相对高渗带。分析认为，影响研究区储层性能的主要因素有沉积作用和成岩作用两种。

Chang-6 reservoirs of Triassic Yanchang Formations are major pay zones in Panguliang-Zhoujiawan area of Ordos basin. Based on the study of sedimentary and petrologic characteristics, reservoir types, pore structures and physical property characteristics, the main factors that influence the reservoirs are analyzed in the paper. Lithology of the reservoir rock in the area is fine-grain arkose and a little part of them is fine lithic arkose. The rock is of low mineral maturity and high structural maturity, and well sorted. Through compaction,cementation and dissolution, the pore types focus＇ on residual intergranular pores and dissolution pores. The general characteristics of the reservoir is low porosity and low permeability with regional high permeability zones. Based on the above analysis, we consider that the main factors that influence the reservoir capability are sedimentation and diagenesis.