柳河盆地早白垩世鹰嘴砬子组沉积及储层发育特征

柳河盆地是受走滑张扭--走滑压扭机制控制的转换伸展盆地。本文以钻井和典型露头剖面为基础,利用成分粒度分析、铸体薄片、扫描电镜、阴极发光及压汞测试等方法,研究鹰嘴砬子组沉积及储层特征。柳河盆地鹰嘴砬子组湖相、扇三角洲相和火山岩相发育,湖盆内碎屑沉积物主要来自盆地西侧和东南侧边缘。盆地内储层的孔渗条件较差,溶蚀和溶解作用对储层起到建设作用,压实和压溶作用、碳酸盐岩的胶结--交代作用、石英的次生加大以及充填作用对储层起到破坏作用。用于物性测试的储层孔渗条件欠佳,整体为Ⅳ类储层。但野外剖面出现的油迹表明鹰嘴砬子组曾发生油气的运移与聚集,显示该盆地存在有致密储层和油气藏,具有油气勘探的潜力。

Sedimentary and reservoir developmental characteristics of Early Cretaceous Yingzuilazi Formation in Liuhe Basin

Liuhe Basin is a transform-extension basin, which is controlled by strike-slip transtensional and strike-slip compressional mechanism. Using the particle size analysis, casting sheet, scanning electron microscope, cathode luminescence and mercury injection, the authors study sedimentary and reservoir characteristics of Yingzuilazi Formation based on drilling data and outcrops. Lacustrine facies, fan delta facies and volcanic facies were developed in Yingzuilazi Formation, Liuhe Basin, and the detrital sediments in the lake basin are mainly from the western and southeastern margin of the basin. Reservoir porosity and permeability are poor in the basin. Dissolution improved reservoir properties, whereas compaction and pressure dissolution, cementation and metasomatism of carbonate, secondary growth of quartz and filling play destructive role on reservoir. The pore and permeability of the reservoir used for physical property testing are poor, and is classified as type Ⅳ reservoir. However, the oil trace in the outcrops indicates that oil and gas migration and accumulation of oil and gas occurred in Yingzuilazi Formation. It shows that there are tight reservoirs in the basin, which have the potential for oil and gas exploration.