琼东南盆地松南低凸起前古近系花岗岩潜山储层特征与控制因素

Reservoir characteristics and controlling factors of Prepaleogene granitic buried-hill in Songnan low uplift,Qiongdongnan Basin

通过壁芯观察、薄片鉴定、储集空间面孔率统计、孔渗分析、测井资料和地震剖面解释等方法,对琼东南盆地松南低凸起花岗岩潜山储层特征和控制因素进行研究。结果表明,松南低凸起花岗岩潜山储层储集空间主要为溶蚀孔隙和裂缝。储层纵向上发育为风化溶蚀带、风化裂缝带和构造裂缝带,风化溶蚀带和风化裂缝带储集物性较好,构造裂缝带储层物性的不均一性较强。潜山储层形成的控制因素包括风化淋滤作用和断裂活动,风化淋滤作用对松南低凸起基岩潜山储层的改造起到积极的作用,断裂活动为基岩潜山储层的发育提供动力条件。

The characteristics and controlling factors of granitic buried-hill reservoirs in the Songnan low uplift of the Qiongdongnan Basin are studied based on wall core observation,thin section identification,face rate statistics of reservoir space,porosity and permeability analysis,logging data and seismic profile interpretation.It is shown that the reservoir space of granitic buried-hill reservoir in Songnan low uplift is mainly dominated by dissolved pores and fractures.The reservoir is longitudinally divided into weathering dissolution zone,weathering fracture zone and structural fracture zone.The weathering dissolution zone and weathering fracture zone have better reservoir physical properties,while the heterogeneity of reservoir physical properties is strong in structural fracture zone.The formation of buried hill reservoir is controlled by weathering leaching and fault activity.The active transformation of bedrock buried-hill reservoir in Songnan low uplift is decided by weathering and leaching.The power required for the development of bedrock buried-hill reservoir comes from fault activity.