松辽盆地砂岩储层的成岩模式与孔隙演化

DIAGENESIS MODEL AND PORE EVOLUTION OF FELDSPAR-RICH SANDSTONE RESERVOIRS IN SONGLIAO BASIN

松辽盆地的油气储层以陆相沉积的富长石砂岩为主,在盆地高地温场的条件下,成岩作用有其独特的模式。本文根据砂岩薄片,X 射线衍射粘土矿物分析,扫描电镜和电子探针,还用显微热台研究了石英次生加大边内气液包裹体的均一温度,阴极发光下成岩矿物定量分析等测试手段。对埋藏深度500—3200m 范围内砂岩储层的成岩标志研究后,建立了富长石砂岩成岩演变模式。将砂岩储层划分出早成岩阶段、中成岩阶段早期、中成岩阶段晚期、晚成岩阶段早期和晚成岩阶段晚期共3个阶段5期。指出松辽盆地白垩系砂岩储层中存在三个次生孔隙发育带。

The oil and gas reservoirs that are mainly composed of continental feldspar-richsandstones in the Songliao Basin have a distinctive diagenesis model due to high geother-mal field of the basin.After the study of diagenetic indication for the sandstone reservoirs buried at thedepth of 500-3200m based on thin section,X-ray diffraction,SEM,electronic probe,the uniform temperature and salinity of the gas-liquid inclusions in the overgrowth ofqartz and the quantitative analysis of diagenetic minerals in cathodoluminescence,this pa-per sets up a diagenetic model of feldspar-rich sandstones,divided the diagenetic evolutioninto 3 stages and 5 phases such as early stage,the early and late phases of the middlestage,the early and late phases of the late stage,and then points out three zones ofsecondary pores.