The distribution and origin of hydrogen sulfide abnormal enrichment coal mines in China

Abstract

Coal mines that contain hydrogen sulfide (H₂S) are widely distributed in China, at present they are mainly located in Zaozhuang in east China, Xin'an, Anyang and Shuangfeng in central China. Qinshui basin, Taiyuan - Liulin areas and Wuhai in north China, Tongchuan-Xianyang area in northwestern China as well as places such as Shizuishan, Houdon, Changji, Liuhuanggou and Sikeshu which belong to Xinjiang, mainly in northwest China, and showed a rapid increase. The contents of H₂S in coal mines changed greatly, from 10 ppm to 5000 ppm. The abnormal coal seams are mainly distributed in the Permian Longtan Formation of southwest China, Permian Shanxi Formation and Carboniferous Taiyuan Formation of east, north and central China, Jurassic Xishanyao and Yan'an Formation of northwest China and so on. The abnormal area have a favorable overlying strata, the hydraulic connection between the underground water and other aquifers are weak, so they are good thick reservoir-seal combination which are beneficial to the origin of Bacterial Sulfate Reduction (BSR) or Thermochemical Sulfate Reduction (TSR). The main origin of H₂S in coal mines are BSR or TSR, and the origin model can be identified synthetically via the tectonic evolution, coal thermal evolution history, isotopic characteristics of carbon and sulfur, methane gas component testing, sulfate sources and sulfate-reducing bacteria activity features.