Abstract:

The oil and gas reservoirs that are mainly composed of continental feldspar-rich sandstones 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 the depth 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 of qartz 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 middle stage,the early and late phases of the late stage,and then points out three zones of secondary pores.