变质岩储层发育的岩相因素分析

Lithofacies Analysis of Metamorphic Reservoir

针对变质岩储层岩石类型复杂、非均质性强、评价难度大的问题,通过对兴隆台潜山岩心观察和岩石化学数据分析,划分变质岩种类,恢复原岩类型并确定了变质相。综合测井、试井资料,分析了变质岩相在潜山中的分布规律,探讨了变质岩相与储层发育的关系。研究结果表明:角闪岩、片麻岩和混合岩为变质岩的主要类型,其原岩为一套泥岩及少量碎屑岩和火成岩,变质程度达中P/T角闪岩相,片麻岩、角闪岩呈层带状分布;混合岩穿插其中,混合岩储集性最好,角闪岩储集性最差。该研究认识对于判别储层性质、分布,指导勘探开发具有重要意义。

Metamorphic reservoir is characterized by complex rock categories,strong heterogeneity and great challenge in reservoir evaluation.Core observation and petrochemical test of Xinglongtai buried hill were used to classify the metamorphic rock,restore original rock category and determine the metamorphic facies.Logging and well test data were combined to analyze the distribution pattern of metamorphic lithofacies in buried hill and discuss the relationship between metamorphic lithofacies and reservoir development.Research indicates that hornblende,gneiss and mixed rock are the major metamorphic categories,and the corresponding original rock is a set of mudstone and a small amount of clastic and igneous rocks.The metamorphism level reaches medium P/T hornblende facies.The gneiss and hornblende show a zonal distribution pattern.The mixed rock intersperses in the gneiss and hornblende.The mixed rock shows the best preservation properties and the amphibolite shows the worst preservation properties.This research could provide certain reference for the characterization of reservoir properties and distribution and also could provide certain guidance for the hydrocarbon exploration and development.