In the bottom of coal measures is an acidic intrusive body, it is direct heat source of metamorphism, and provided the conversion of lignite to bituminous coal with thermodynamic power.
在本区煤系地层底部有一酸性侵人岩体，该侵入岩体是引起本区煤变质的直接热源，它提供了褐煤向烟煤转化的热动力。
In the bottom of coal measures is an acidic intrusive body, it is direct heat source of metamorphism, and provided the conversion of lignite to bituminous coal with thermodynamic power.
在本区煤系地层底部有一酸性侵人岩体，该侵入岩体是引起本区煤变质的直接热源，它提供了褐煤向烟煤转化的热动力。
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