Study On Metamorphism Of Deep-Seated Coal In Huainan Coal Field

The understanding of coal characteristics was based on the study to the shallow coal seam in coal geology for a long time. But the project jumped out the understanding of the traditional theory of coal geology to study the metamorphism of deep-seated coal in Huainan coal field using the analysis methods of coal petrology and coal chemistry, and the controlling geological factor of increase in metamorphic grade of deep-seated coal was analyzed, then the typical identification mark of coal petrology of telemagmatic metamorphism had been established.The relationship between coal metamorphic indicators (carbon content, hydrogen content, volatile matter) and depth had been researched by using regression analyses with a large number of testing information of coal quality in Huainan coal field, and the results showed that, with the increase of depth, coal metamorphic grade in Huainan coal field increases linearly. The regularity of the plutonic metamorphism was obvious.Based on the results of qualitative and quantitative analysis of plutonic metamorphism, modern depth played an important role in the increase of deep-seated coal rank in Huainan coalfield, but the affect of modern depth on coal metamorphism was different in each mine in Huainan area, with the statistical result of thickness data of drilling loose bed,it found that loose bed from thin to thick, the change of metamorphic grade with depth from strong to weak, this also explained why that when the depth was same but the metamorphic grade was different(thickness of loose bed was different).so the starting line of affect of depth to metamorphism of deep-seated coal in Huainan should be deducted the thickness of surface loose layer counting from rock head, the increase of metamorphic grade of deep-seated coal in Huainan coalfield was mainly caused by the effect of the depth from rock head to coal seam(modern depth deducted thickness of loose bed).By means of optical microscopy, coal macerals of typical magmatic thermal metamorphism in Huaibei was observed using coal petrology research methods, "Marker" (anisotropic body) of magmatic thermal metamorphism coal had been established. And contrast microscopic components of coal in Huainan coalfield, the role of magmatic heat influence to the coal in Huainan coalfield was excluded from the view point of coal petrology. According to metamorphism type of coal and the laboratory data of coal quality in Huainan coalfield, the zonage of coal types along the stratigraphic sequence and along the same coal seam with depth had been studied, and the zonage of coal rank along vertical depth had been projected.Figure [53] table [28] reference [81]...