A Study on Triassic Shale Gas Reservoir Characteristics from Ordos Basin

摘要

The Triassic continental shale from Ordos basin was selected as the research object, through the analysis of X-ray diffraction (XRD), field emission scanning electron microscopy (SEM) and nitrogen adsorption experiment, the mineral composition and pore structure characteristics of Triassic continental shale from Ordos basin have been investigated in detail. X-ray diffraction analysis result shows that the mineral composition is mostly composed of clay minerals and silica minerals, with minor contributions made by carbonate minerals. The clay mineral content ranges from 40.5% to 66.0% with an average of 55.8%, and the silicoide mineral content accounts for 22.4% to 58.3%. Compared with marine shale gas reservoir, Triassic continental shales from Ordos basin are characterised by high clay mineral content. The shale samples show high specific surface areas of 1.1～22.9 m~2·g~(-1).