黄骅坳陷北部上古生界碎屑岩储层特征及差异性

摘要

The reservoir types of NeoPaleozoic in the north of Huanghua depression are widely developed,and the clastic reservoir is the most widly developed.Based on the data of drilling core,rock slice,physical property test and XRD total rock diffraction,the characteristics and the difference of NeoPaleozoic reservoir in Huanghua depression are systematically studied.The results show that the lithology of XiaShihezi Formation is mainly composed of medium and coarse grain quartz sandstone and feldspar lithic sandstone,which is high porosity and high quality reservoir, and the reservoir space is dominated by leaching and scouring holes. The lithology of Shanxi formation is mainly fine grained fine sandstone,relatively dense reservoir,and reservoir space is mainly fractured,and the cementation degree of carbonate rock is high. The lithology of Taiyuan formation is mainly fine grained tuffaceous sandstone, which is low porosity and low permeability reservoir,and the reservoir space is mainly fractured and tuffaceous dissolved pore.The differences among every formation are mainly embodied in the reservoir lithology in different sedimentary and diagenetic environment caused by the transformation of the role of the reservoir differences,Xiashihezi formation by weathering and leaching of thick layer of coarse sandstone facies reservoir of river is the best performance, Taiyuan formation by devitrification and dissolution of the tuffaceous sandstone reservoir performance the compaction and cementation group is tighter than Xiashihezi formation,the compaction and cementation of the Shanxi formation make it more compact.%黄骅坳陷北部上古生界碎屑岩储层发育广泛,不同层位具有明显的差异性.综合利用钻井岩心、岩石薄片、铸体图像、扫描电镜、物性及XRD等测试分析,对黄骅坳陷上古生界储层特征进行了系统研究,并分析了储层差异性因素.结果表明:下石盒子组岩性以中、粗粒石英砂岩、长石岩屑砂岩为主,为高孔渗优质储层,储集空间以淋滤冲刷孔为主;山西组岩性以细粒岩屑细砂岩为主,较为致密储层,储集空间以裂缝为主,碳酸盐岩胶结程度较高;太原组岩性以细粒凝灰质砂岩为主,为低孔低渗储层,储集空间以裂缝与凝灰质溶孔为主.各组储层之间差异性主要体现在不同沉积环境造成的岩性差异与成岩作用对储层的改造差异,下石盒子组受风化淋滤作用的厚层河道粗砂岩相储集性能最好,太原组受脱玻化作用与溶蚀作用的凝灰质砂岩储集性能次之,山西组压实作用与胶结作用发育导致其较为致密.