Geological characteristics and gas potential analysis of the Biluocuo oil shale in the southern Qiangtang Basin, China

Abstract

ABSTRACTShale gas exploration in the Qinghai–Tibet area has lagged behind as compared to the other regions of China, and no shale gas reservoir has been discovered till yet. The analysis of the geological and reservoir characteristics of the Biluocuo oil shale samples from the southern Qiangtang Basin indicates the following findings. The oil shale has a high organic matter content, and the average mass fraction of organic carbon is 4.62%. Additionally, the organic matter is type II. The thermal evolution of organic matter has reached from a low to a high mature stage, and the porosity and permeability are 1.25% and 0.0102 mD, respectively. The rocks are highly brittle, and the primary mineral components are calcite and quartz, whose average contents are 58% and 22%, respectively. Moreover, the rock has a high adsorption capacity. Furthermore, a comparison with the five major shale gas systems in North America found the following. The Biluocuo oil shale is similar to the Barnett shale and Ohio shale, particularly to the Barnett shale. This comprehensive analysis indicates that the Biluocuo oil shale has considerable gas potential and is a key formation for shale gas exploration in the Qinghai–Tibet area.