The Characteristics of Deep-Seated Coal Seam in Wangfenggang Mine Huainan Coal Field

With the increase of coal demand, most coal fields in North China have developed their deep-seated coal seam, and it is important to have a full understanding of characteristics of the coal in deep seam. The coal petrology as well as the distribution characteristics of coal quality of the deep-seated coal seam in Wangfenggang mine field in Huainan area was studied in this paper. The influence exerted by the regional geothermal and tectonic subsidence history on regional coal metamorphism process was also considered in the study. It is found that coal metamorphism process could be affected by the tectonic stress energy. The results of the study show that the development of the metamorphisms is consistent with coal seam structural shape in a series of bituminous coal band, which includes gas coal, 1/3 coking coal, fat coal and lean coal vertically distributing in the deep seated seam (-600 m ~ 1200 m). It has been deduced that the metamorphism type of Wangfenggang mine field is the superposition of deep seated metamorphism and energy transformation from tectonic stress on hydrostatic pressure state. This means coal metamorphism has been promoted and controlled by long term regional extrusion. The study on the rule of coal metamorphism on deep seated seam can be expected to help the exploration of coking coal in China and to amend the present metamorphism theory.