新疆艾维尔沟煤变质作用研究

新疆艾维尔沟矿区是侏罗纪天山褶皱带中的一个小型山间含煤盆地。多项煤变质指标的分析结果表明:该区煤级在横向上分带明显,垂向上煤级突变,煤岩组份中出现热变显微组份,煤晶核指标(La/Lc)大于1,矿区广泛发育热液石英脉和方解石脉,煤层围岩也具有中低温热液蚀变现象。所有这些特征都充分表明,艾维尔沟的煤变质属区域热变质类型。推测其附加热源位于该煤盆地西部,地下水热液的对流为主要热传导方式。矿区及其外围的构造、地层结构、地势、水文等条件均有利于地下水热液循环。

STUDY OF COAL METAMORPHISM AT EWIRGOL, XINJIANG

Ewirgol mine field in Xinjiang is a small coal-bearing intramountain basin of Jurassic within Tianshan fold zone. Analytic results show that the coal metamorphic zonation is clear horizontally and abrupt vertically. Thermal metamorphic macerals appear in coal petrology, with coal crystallite index (La/Lc)>l. The veins of hydrothermal quartz and calcite, are extensively developed in the mine field. The middle-low temperature alterations also occur in the country rocks of coal steam. All these features reveal that the coal meta-morphism in Ewirgol belongs to a regional thermal type. The assumptions show that the additional heat resources come from the west of the coal-bearing basint and the heat is mostly transferred by underground thermal water . The structure, stratigraphic texture, topography and hydrology of the mine field and its surroundings are favourable for the circulation of underground thermal water.