苏北盆地金湖凹陷碳酸盐岩孔隙类型及孔隙结构特征

在岩心观察基础上,根据铸体薄片、压汞等资料,对苏北盆地金湖凹陷碳酸盐岩的岩石类型进行了细分,并研究了其孔隙类型、孔隙结构特征及影响因素。研究结果表明,研究区以生物碎屑灰岩、鲕粒灰岩为主,溶蚀孔发育,喉道分布不均匀,局部孔喉很发育,甚至呈蜂窝状或管状,是比较好的储集层段,但其它部位又存在岩性致密、孔隙度小、喉道细,连通性较差的情况。岩性、沉积环境、成岩作用是该区孔隙结构的主要影响因素。

Pore type and pore structure characteristics of carbonate reservoirs in Jinhu depression,Subei basin

Based on the core observation,according to cast thin,mercury injection and other information,the subdivision of Carbonate rock types and the studies of the its pore type,pore structure characteristics and influencing factors have been carried out.The study results indicate the study area is mainly of bioclastic limestone and oolitic limestone,with developed dissolved pores,uneven distribution of pore throats.Locally the pores are better reservoir segment,presenting honeycomb or tubular.In other parts,the lithology is dense,with small porosity and fine throat,being of poor connectivity.Therefore,lithology,sedimentary environment and diagenesis are the main factors affecting the pore structure.