Abstract:The chemical composition, physical property, structural evolution and mineralogical characteristics of magmatic metamorphic coal in the Hanpoao coal mining area of the Hunan Province were investigated by XRF, DTA, SEM, HRTEM, XRD and Raman analytical methods. The results show that the magmatic thermal metamorphism and tectonic stress promoted anincreasing degree of coalification that gradually resulted in transformation into cryptocrystalline graphite. With an increase of coal rank, the ratio of hydrogen to carbon atoms in coals decreased. The major mineral components in samples include illite, chlorite, pyrophyllite, quartz and pyrite. With an increase in the degree of metamorphism, the true density increases and the porosity and resistivity decrease. After 400 ℃, the weight loss curve decreases slowly and the slope decreases, indicating less deep cracking and shedding. With an increase of coal rank, the stack height and diameter increase, the evolution of organic macromolecular structure of coal near the magmatic intrusion shows an obvious jump; the graphite samples are mainly of 2Hgraphite, and contain 3Rgraphite in varying degrees; the graphitization degree is 0. 47~0. 84. The graphite crystal axial length a is 0. 2469~0. 2471 nm, c is 0. 6738~0. 6762 nm, and the crystal cell volume V is 0. 03562~0. 03570 nm3, indicating that the crystal cell volume near the rock mass decreases. With the increase of the metamorphic degree, L a and L c increased rapidly, and the number of stacked layers increased sharply. The internal spatial structure of coal tended to be orderly, and Raman parameters A D1 and P (G- D1) gradually decreased.