子洲地区北部下二叠统山2段储层特征及其形成机理

通过对鄂尔多斯盆地子洲地区北部下二叠统山2段铸体薄片、扫描电镜、压汞及测井等资料的分析,研究了其储层特征及形成机理。结果表明:研究区山2段储层主要发育石英砂岩和岩屑砂岩;山23亚段储集空间主要为粒间孔-溶孔,山22和山21亚段储集空间主要为微孔;研究区储层属于低孔、低渗型;三角洲前缘水下分流河道是形成储层的主要相带,储层特征受控于沉积作用、成岩作用、孔隙结构类型及其组合形式;研究区强烈的压实-压溶作用及胶结作用是导致储层孔隙度与渗透率低的主要原因。

Reservoir characteristics and formation mechanism of Lower Permian Shan 2 member in northern Zizhou area, Ordos Basin

Based on the analysis of cast slices, scanning electron microscope, mercury injection test and well logging, this paper studied the physical properties and formation mechanism of Shan 2 member in northern Zizhou area, Ordos Basin. The result shows that the reservoir of Shan 2 member mainly developed quartz sandstone and lithic sandstone. The reservoir spaces are mainly intergranular pores and dissolved pores of PI sh23, and micropores of P1sh2 and Plsh2l reservoirs. The reservoir belongs to low porosity and low permeability reservoir. Delta front suhaqueous distributary channel is the main facies belt for forming reservoirs. The reservoir properties are controlled by sedimentation, diagenesis, pore structure types and its combination patterns. The physical properties were mainly reduced by compaction- pressolution and cementation.