区域岩浆热变质作用及其对我国煤质的影响

本文根据中国煤变质的特点分析了促使煤变质演化的地质条件,阐述了接触变质作用和动力变质作用的局限性,主要是深成变质作用使中国煤演化到低变质阶段,燕山期岩浆活动导致的区域岩浆热变质作用弥补了这一缺点,使很大一部分中国煤增高了煤级,形成了储量丰富,多用途的中、高变质煤。并根据岩浆性质、侵入规模、侵入层位和深度以及沉积盖层的封闭程度对区域岩浆热变质作用进行分类,划分出三个亚型:深成岩浆热变质作用、中深成岩浆热变质作用和浅成岩浆热变质作用,总结了区域岩浆热变质作用的鉴定特征及其对中国煤质的影响。

Telemagmatic Metamorphism and its Effects on Chinese Coal Properties

In view of the characteristics of the Chinese coal metamorphism, the effects of contact metamorphism and dynamic metamorphism are analysed. The telemag-matic metamorphism is newly classified again into three subtypies based upon the magmatic characters, intrusive scale, the strata and depth intruded and the confining conditions in the covering strata of coal seams. The distinct features of telemagmatic metamorphism are summarized.Chinese coals metamorphosed mainly to low ranks only through geothermal metamorphism. It is the Yanshan magmatic activities during the activation of Chinese plateform that provoked the telemagmatic metamorphism which raised the coal ranks and forming most of the middle and high ranking coals in China.