准噶尔盆地石炭系火山岩储层主控因素分析

通过对准噶尔盆地石炭系火山岩油气藏岩芯的详细观察以及对储层岩石物性数据的统计分析,认为构造运动、岩性与岩相、风化淋滤作用是控制准噶尔盆地石炭系火山岩储层的主要因素。火山岩储集空间类型分为原生裂缝、原生孔隙、次生裂缝、次生孔隙四类。储层的渗流能力主要由裂缝决定。风化壳是准噶尔盆地石炭系火山岩储层的主要类型。优质储层主要分布在风化壳顶面以下250 m距离以内,其中环坳陷分布的古隆起部位更为有利。距离风化壳顶面越远,孔隙和裂缝充填程度越高,火山岩储集性能越差。

Analysis of Predominant Factors of Volcanic Reservoirs in Carboniferous of Junggar Basin

According to the core observation and statistics of physical properties,it is found that weathering,tectonism,lithology and litho-facies are the predominant factors of volcanic reservoirs in Carboniferous of Junggar Basin.The reservoir space includes primary fractures,primary porosity,secondary porosity and secondary fractures.The permeability is mostly controlled by fractures.Weathering crust is the main reservoir of volcanic rock in Carboniferous.High quality reservoirs are mainly located 250 m from the top of weathering crust.Among all the high quality reservoirs,the paleohigh around the depression is the better position.As the distance from the top of weathering crust increases,the filling degree of fractures as well as porosity becomes higher and this degrades the reservoir quality.