湘西北地区震旦—三叠系储层特征及分布规律

石门—桑植震旦系—三叠系地层中发育的储层主要包括两大类，即碳酸盐岩和砂岩。在对大量普通薄片、铸体薄片详细观察研究的基础上，根据孔隙的成因及结构，将石门—桑植震旦系—三叠系储层的储集空间划分为：原生残余粒间孔、次生粒间溶孔、次生粒内溶孔、窗格孔隙、超大溶蚀孔、裂缝。通过储层物性特征分析，认为沉积作用及成岩后生作用是该区储层物性的主控因素。其中沉积相对储层物性的好坏起着决定性作用。研究结果表明该套地层中的储层类型多样，但储层物性较差，多数为低孔、低渗储层，只有上三叠统鹰嘴山组中的砂岩储集性能较好。

THE CHARACTERISTICS AND DISTRIBUTION OF THE RESERVOIRS FROM SINIAN TO TRIASSIC IN NORTHWEST HUNAN

Reservoirs in Shimen-Sangzhi from Sinian to Triassic mainly include two categories，namely，carbonate rocks and sandstone.On the basis of observation and detailed study on a large deal of common and casting rock thin section，the reservoir space in Shimen-Sangzhi from Sinian to Triassic is divided into primary remaining intergranular pore，secondary intergranular dissolution pore，secondary intragranular dissolution pore，pane pore，super large dissolved pore and cracks according to the structure and cause of the pores.Sedimentation and late diagenesis are found to be the main control factors of reservoir physical property in the area through analysis of the characteristics of reservoir physical property.And the influence of sedimentary facies on reservoir physical property is decisive.Accordingly，reservoir distribution is summarized.Generally speaking，in this set of formation，there are various types of reservoirs，but with poor reservoir physical properties，low porosity and low permeability reservoirs are dominant，except that the sandstone in the upper triassic Yingju formation is of good reservoir property.