The higher the degree of coal metamorphism is, the better the conductivity of coal is and the clearer the electric effect of methane gas in coal is.
煤化程度越高的煤导电性越好，且甲烷气体在煤中的电动效应越明显；
Research shows that maceral and the degree of metamorphism of coal rock are key factors that control the generating and storing capacity of coal rock.
煤岩组分和煤变质程度是影响煤层生储气能力的主控因素。
As to the coal seams with complex texture and higher degree of metamorphism, the qualitative division of coal species is more complex.
对于煤层结构复杂、变质程度较高的煤类，定性分类较为复杂。
As to the coal seams with complex texture and higher degree of metamorphism, the qualitative division of coal species is more complex.
对于煤层结构复杂、变质程度较高的煤类，定性分类较为复杂。
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