Mineral characteristics and geological significance of coal gangue in Hanpoao Coal Mining Area, Hunan Province

被引：0
|
作者：
Li H. [1 ,2 ]
Zhang W. [1 ]
Wang N. [1 ]
Pan Y. [1 ]
Chen Y. [1 ]
机构：
[1] College of Geology and Environment, Xi’an University of Science and Technology, Xi’an
[2] Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi’an
来源：
Meitan Kexue Jishu/Coal Science and Technology (Peking) | 2022年 / 50卷 / 04期
关键词：
coal gangue; coal measure graphite; Hanpoao Coal Mining Area of Hunan Province; illite; mineral characteristics;
D O I：
10.13199/j.cnki.cst.2020-1526
中图分类号：
学科分类号：
摘要：
The increase of coal metamorphism and the transformation of minerals in the gangue are closely related to the change of the surrounding deformation environment.The mineralogy characteristics and illite crystallinity of coal gangue in Hanpoao Coal Mining Area of Hunan Province were studied by means of polarizing microscope and X-ray diffraction (XRD).The characteristics of clay minerals directly or indirectly indicate the degree of coal metamorphism and its response to temperature and pressure changes were discussed.The results show that the clay mineral, a layered silicate mineral, is very sensitive to the change of deformation environment in the study area. The andalusite (chiastolite) in the coal seam is symbiosis with illite, phyllite and chlorite, etc.The crystallinity of illite is high, and the crystallinity is distributed in 0.140 6° ~ 0.090 9°⃤2θ, the average crystal thickness (Lc) is greater than 566×10-1 nm.The crystalline order degree of illite was consistent with the organic structural evolution, compared with the peak area, half height and width of illite (001) and the γ peak of irregular part.Vitrinite reflectance and Raman spectra of coal geological thermometer revealed graphite formation of the metamorphic temperature of 400~ 500 ℃ or higher, indicating the study area of coal seam by low-level epimetamorphism, illite in coal gangue is more than 2M1 model, b0 distributed in 8.883 6 ~ 9.030 5×10-1 nm, indicates the deformation environment of coal seam and surrounding rock under low and medium pressure, the pressure conditions formed are 250~400 MPa or higher.According to the change of XRD structure parameters of coal with different metamorphism degree with formation temperature, it shows that higher heating condition is an important factor of organic matter evolution and mineral transformation in gangue.However, the d002 spacing of organic matter structural basic units in coal continues to decrease in the range of similar temperature changes, indicating that the strong tectonic stress in the geological process can catalyze the graphitization process significantly. © 2022 Meitan Kexue Jishu/Coal Science and Technology (Peking). All rights reserved.
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页码：206 / 212
页数：6
相关论文
共 19 条
  • [1] GUIDOTTI C V, SASSI F P., Classification and correlation of metamorphic facies series by means of muscovite b0 data from low grade metapelites[J], Neues Jahrbuch für Mineralogie Abhandlungen, 153, pp. 363-380, (1986)
  • [2] BI Xianmei, MO Xuanxue, Transition from digenesis to low grade metamorphism and related minerals and energy resources, Earth Science Frontier, 11, 1, pp. 287-294, (2004)
  • [3] AOYA M, KOUKETSU Y, ENDO S, Et al., Extending the applicability of the Raman carbonaceous - material geothermometer using data from contact metamorphic rocks[J], Journal of Metamorphic Geology, 28, 9, pp. 895-914, (2010)
  • [4] HU Daqian, HAN Chunyuan, MA Rui, Et al., The very low grade metamorphism in the Upper Paleozoic in Xinlingol area of Inner Mongolia, NE China:Evidence from studies of illite and vitrinite reflectance, Acta Petrologica Sinica, 28, 9, pp. 3042-3050, (2012)
  • [5] Ren Leifu, Chen Yunjing, On the devision of diagenesis stages according to the transformation of clay minerals, Oil& Gas Geology, 5, 4, pp. 325-334, (1984)
  • [6] LI Xiaoming, CAO Daiyong, The structural evolution character of different types of coal metamorphism and its geological significance, Journal of China University of Mining & Technology, 41, 1, pp. 74-81, (2012)
  • [7] LI Huantong, WANG Nan, ZHU Zhirong, Et al., Raman spectrum characteristic and structural evolution of high rank coals - cryptocrystalline graphite, Coal Geology & Exploration, 48, 1, pp. 34-41, (2020)
  • [8] LI Huantong, CHEN Fei, ZOU Xiaoyan, Et al., Effect of intrusion of the Tianlongshan Granite Body on coal seam deformation and metamorphism characteristics in Xinhua Area, Hunan Province, Journal of China Coal Society, 44, 7, pp. 2206-2215, (2019)
  • [9] LI Huantong, WANG Nan, ZHU Zhirong, Et al., structural evolution and mineralogical characteristics of magmatic metamorphic coals in Hanpoao coal mining area, Hunan Province, Acta Geologica Sinica, 94, 11, pp. 3503-3514, (2020)
  • [10] BUSTIN R M, ROSS J V, ROUZAUD J N., Mechanisms of graphite formation from kerogen: experimental evidence [J], International Journal of Coal Geology, 28, 1, pp. 1-36, (1995)
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