鄂尔多斯盆地王洼子地区长4+5、长6储层特征及主控因素

王洼子地区长4+5、长6储层岩石类型以岩屑长石砂岩为主,孔隙类型以粒间孔为主,长石溶孔次之。储层总体表现为中–低孔超低渗储层,其中长(4+5)2储层物性相对较好,长61、长62次之,孔渗分布均表现为单峰值特征。储层受成岩作用影响大,压实作用是储层变差的主要因素,其次为胶结作用,溶蚀作用是储层物性改善的主要因素,绿泥石的发育对孔隙的保存与储层渗透性起到积极作用,高岭石发育是促进次生孔隙发育的重要因素。

Reservoir characteristics and main controlling factors of Chang 4+5 and Chang 6 reservoirs in Wangwazi area of Ordos Basin

The rock type of Chang 4+5 and Chang 6 reservoirs of Wangwazi area is mainly of lithic feldspar sandstone and the pore type is mainly of intergranular pore,secondarily of feldspar dissolved pore.The reservoirs are generally expressed as medium-low porosity and ultra-low permeability,in which the physical properties of Chang(4+5)2 reservoirs are relatively good,followed by Chang 61 and Chang 62,and the porosity and permeability distribution is characterized by single peak value.The reservoirs are greatly affected by diagenesis,compaction is the main factor of reservoir variation,followed by cementation.Dissolution is the main factor to improve reservoir property,the development of chlorite plays a positive role in the preservation of porosity and reservoir permeability,and the development of Kaolinite is an important factor to improve the development of secondary porosity.