准噶尔盆地小拐地区佳木河组储层特征及主控因素

小拐地区佳木河组属低孔、低渗储层,为明确该区储层的主控因素,根据岩心观测、薄片鉴定、分析化验等结果,研究其沉积特征、储集空间、物性特征、成岩作用等.结果表明:小拐地区佳木河组为一套巨厚陆上冲积扇—扇三角洲复合沉积,岩石颗粒组分复杂、成熟度低,储层主要储集空间包括界面孔、微裂缝、溶蚀孔、构造裂缝等;储层受裂缝—孔隙双重介质影响,非均质性强.该区构造裂缝较为发育,以构造成因的直立剪切裂缝为主,对储层改造具有重要作用,裂缝发育情况与油气显示及产能密切相关;该区储层发育的主控因素包括岩性岩相、构造运动、成岩作用等.该区岩性岩相是控制储层发育的根本条件,构造运动产生的主控断裂有利于油气运移与聚集、强化储层裂缝发育,成岩作用中的溶蚀作用有效改善区内储层储渗性能.

Reservoir characteristics and dominant factors of Jiamuhe formation in Xiaoguai area of Junggar basin

The reservoir of Jiamuhe Formation in Xiaoguai area belongs to the low porosity and low permeability reservoir.In order to determine the domain factors of the reservoir,sedimentary characteristic,reservoir space,physical characteristic and diagenesis are studied by coral observation,section identification and analysis of laboratory.Study shows that Jiamuhe Formation in Xiaoguai area is a series of thick alluvial fan-fan delta complex deposition,with complex rock particles component and low maturity.The main reservoir space includes interface holes,micro-cracks,corrosion holes,structural cracks.Influenced by the dual media of cracks and porosity,the reservoir produces strong heterogeneity.Structural cracks in the region are well developed,most of which are the vertical shear fractures with the constructing causes.The presence of cracks has an important role in the development of the reservoir.The cracks development is closely related with oil and gas show and capacity.The majority of controlling factors of reservoir development include lithology(facies),tectonic movement,diagenesis and so on.Lithology(facies) is the fundamental condition to control the reservoir development.The master fractures caused by the tectonic movement are conducive to oil and gas’s migration and accumulation,while strengthening the development of cracks in the reservoir.Besides,corrosion of diagenesis improves the permeability of the reservoir in the region effectively.