苏里格气田储层成岩序列与孔隙演化

采用盆地模拟技术、流体包裹体及其它地球化学分析技术、对比分析方法和综合研究方法对苏里格气田储层成岩序列与孔隙演化进行了研究。结果认为苏里格气田下二叠统下石盒子组和山西组储层现今处于晚成岩A阶段，部分处于晚成岩B阶段。由于沉积阶段水体能量的差异和埋藏阶段成岩作用的不同，气层和非气层的成岩序列和孔隙演化模式存在较大差异。储层孔隙演化的影响因素主要包括构造条件、沉积相、成岩作用等，沉积条件是基础，成岩作用是关键，构造演化史和埋藏史是动态影响因素。由于沉积物质基础不同，后期成岩演化和构造条件不同，可以导致不同储层之间物性的较大差异。在成岩演化晚成岩A阶段，大量有机酸的排出，溶蚀了凝灰质和长石等易溶组分，形成了有利储集成岩相带--较低孔低渗储层中的“甜点”。

RESERVOIR DIAGENETIC SEQUENCE AND PORE EVOLUTION OF SULIGE GAS FIELD IN E'ERDUOSI BASIN

On the basis of studying reservoir diagenetic sequence and pore evolution, the reservoir pore evolution mode and control factors of Sulige gas field are approached by the means of basin simulation, fluid inclusion, geochemistry analysis and correlation analysis. It is considered that the reservoirs of Lower Shihezi Formation and Shanxi Formation of Permian Series in Sulige gas field are at the stage of late diagenetic A and partially are at the stage of late diagenetic B. The diagenetic sequence and pore evolution of gas zone are very different from those of non gas zone owing the differences of the water energy at sedimentary stage and the diagenesis at burial stage. The influence factors of reservoir pores mainly include structural conditions, sedimentary facies, diagenesis etc. Among them, sedimentary condition is the foundation; diagenesis is the key factor; structural evolution history and burial history are the dynamic influence factors. The differences of sedimentary materials, diagenetic evolution at lat stage and structural conditions can bring about considerable diversities among the physical properties of various reservoirs. A vast amount of organic acid discharged at the stage of late diagenetic A denuded tuff, feldspar etc. to form the “sweet point” in the favorable diagenetic facies zone the reservoirs with lower porosity and permeability. (Financed by the National Basic Research Program project, No. 2001CB209103)