Lithologic characteristics and diagenesis of the Upper Triassic Xujiahe Formation, Yuanba area, northeastern Sichuan Basin

摘要

The Upper Triassic Xujiahe sandstone in the Yuanba area, northeastern Sichuan Basin, is a typical coal bearing tight gas reservoir. Whether or not the commercial production of gas from these tight sandstones can be achieved largely depends on the quality of the reservoirs. In this study, a petrographic analysis using a thin section and a scanning electron microscope (SEM), combined with reservoir property data, was carried out to discuss the effects of primary mineral compositions on diagenetic processes and reservoir quality.