白豹-坪庄地区长63储层有利区块预测

Prediction of favorable areas of  Chang 63 sandstone reservoir in  Baibao-Pingzhuang Area

杨映涛1 ,陈恭洋2, 张路崎2 ,苏 洁

1．中国石化西南油气分公司勘探开发研究院，四川 成都 610081 2．长江大学地球科学学院，湖北 荆州 434023

1．Exploration and Development Research Institute, Southwest Oil and Gas Company, SINOPEC, Chengdu 610081, China School of Geosciences, Yangtze Unversity, Jingzhou 434023, China

根据铸体薄片、扫描电镜、岩心、测井等资料研究结果，长63储层经历了复杂的成岩作用，储层物性差， 属于中低孔特低渗储层，储集空间以剩余粒间孔和溶蚀孔为主，成分成熟度低，结构成熟度中等—较高。储层质量受到沉积微相和成岩作用的双重控制，沉积微相控制着储层原生孔隙的发育，成岩作用控制着次生孔隙的发育，三角洲前缘水下分流河道水动力条件较强，沉积的碎屑物粒度相对较粗，分选好，是最有利于储层发育的沉积微相；长石溶蚀成岩相以长石溶孔发育为主要特征，长石沿解理面溶蚀强烈，次生孔隙发育，储层物性显著变好，是该区最有利的成岩相；碳酸盐胶结物溶蚀成岩相较长石溶蚀成岩相溶蚀程度低，孔隙中的铁方解石、铁白云石胶结增多，物性相对较好，是该区较有利的成岩相；绿泥石衬垫式胶结成岩相以绿泥石衬垫式充填孔隙为主要特征，胶结作用相对较弱，孔隙类型以剩余粒间孔隙为主，储层孔渗性较好，也是该区较有利的成岩相。根据沉积微相和成岩相，三角洲前缘水下分流河道和长石溶蚀成岩相、碳酸盐胶结物溶蚀成岩相以及绿泥石衬垫式胶结成岩相的叠置发育区即为该区储层有利区块。

 Based on the studies of casting thin section, scanning electron microscopy, cores, it is  indicated that Chang 63 sandstone reservoir has experienced complex lithogenesis, causing the reservoir with low to medium porosity and extraordinary low permeability. The reservoir space are of mainly residual intergranular pore and corrosion pore. The compositional maturity is low and textural maturity is medium to high. The reservoir are effected by sedimentary microfacies and diagenesis, sedimentary microfacies control the development of the primary pore and diagenesis controls the development of the secondary pore. The underwater distributary channel in delta front has strong hydrodynamic condition, and the detrital materials are relatively coarse and well sorting, which is the best sedimentary microfacie favorable for the development of good reservoir. The development of feldspar dissolved pore is the main characteristic of feldspar dissolution diagenetic facies, in which feldspar has strong corrosion along the cleavage face and secondary pores are developed causing the reservoir′s physical property become better. It is the best diagenetic facies in the area. Compared with feldspar dissolution diagenetic facies, carbonate cement dissolution diagenetic facies have lower dissolution of feldspar, with more cementation of ferrocalcite and ankerite, having relatively better physical property, which is the relatively better diagenetic facies in the area. Cementation of the chlorite padding diagenetic facies have weaker cementation whih the chlorite filling the pore as its main characteristics. The pore types are mainly residual intergranular pores with better porosity and permeability. It is also relatively better diagenetic facies in the area. Based on the sedimentary microfacies and diagenesis facies, The overriding area of the underwater distributary channel in delta front, feldspar dissolution diagenetic facies, carbonate cement dissolution diagenetic facies and cementation of the chlorite padding diagenetic facies are the favorable areas of reservoir.