The vitrinite reflectance test value of each minable seam in this area (level 2) is 0.69 ~ 1.04, which belongs to the grade ii ~ iii metamorphism stage of medium coal. some sections of coal seam 1 are eroded and degenerated into natural coke by magmatic rocks, and its vitrinite reflectance reaches 4.62, as shown in table 4-2-2.