中国煤变质作用

通过煤变质热源及作用方式的研究，总结了中国煤变质作用主要类型，动态地史－热史模拟表明，煤盆地的地热状态以非均－地温场影响深成变质格局，如鄂尔多斯盆地三叠纪的地温高于前后时代，大地热流同盆地了中心增高，四川盆地中心莫霍面较浅，与高变质煤分布基本一致，区域岩浆热变质是形成中国大多数中高煤级煤的主因，模拟分析了湘赣中南部印支－燕山期花岗岩体与煤变质，煤热水变质作用以载热的深循环流体构成派生热绿岩侵入的增

COAL METAMORPHISM IN CHINA

The predominant coal metamorphism types in China are summed up throuth the study of the heat source and its operating mode on coal metamorphism. The dynamic simulation of geologic thermal history shows that the geothermal state of coal basins influenced the geothermal metamorphism pattern of coal with inhomogeneous geotemperature field. For example in Ordos basin, not only the Triassic geotemperature was obviously higer than that of the previous or later and also the geothermal flux increased from the margin to the center of the basin. The basement of Sichuan basin is relatively plastic, and towards its center the Moho depth is shallower, which is on the whole in accordance with the medium high rank coal distribution. The telemagmatic metamorphism is the main cause for the formation of the lager number of medium high rank coals in China. The coal metamorphism provoked by magma intrusion during the Indosinian and Yanshanian in central southern Hunan and Jiangxi Provinces is simulated. Deep circulating fluid as the heat carrier constructs the induced heat source of hydrothermal metamorphism. The paleo Moho temperature during the rifting of the Fushun basin is determined and the coal rank through diagenesis in the basin is calculated, which reaches the low rank bituminous stage owing to the later intrusion of diabase magma. The non equilibrium heat conduction model of multilayer plate during the heat dispersion of the diabase sill is set up. Also worked out is the Yongan coal rank, located in the superimposed basin of Fujian Guangdong, which was formed by deep metamophism and additive magmatic metamorphism. The metamorphism regulatrities of Chinese coals mainly are:in the tectonic stable region, the coal metamorphism characterized by the nature of inherited development; the geothermal background of coal metamorphism displaying the obvious space time changes; in mlti heat sources and multi period superimposed metamorphism influence profoundly over the evolution of Chinese coal metamorphism especially the telemagmatic metamorphism since Yanshan orogeny have evidently reformed the Chinese coal marks; the Tertiary tectonic displacement brought about the distribution frame of the Chinese coal rank zonation.