抚顺煤的有机地球化学特征及煤相浅析

THE ORGANIC GEOCHEMISTRY CHARACTERISTICS AND COAL FACIES ANALYSIS OF DIFFERENT COAL LITHOTYPES IN FUSHUN COAL FIELD

抚顺煤田西露天矿主煤层有三种代表性煤岩类型。煤岩学和有机地球化学研究结果表明,光亮煤富镜质组和树脂体,倍半萜和二萜类异常丰富。半亮煤富含惰性组分和藿烷,混合煤富壳质组分和藿烷,正构烷烃呈双峰型。混合煤为Ⅱ-Ⅲ型干酪根,半亮煤和光亮煤属Ⅲ型干酪根。根据以上结果,结合古植物和孢粉化石资料以及显微组分的细胞结构特征推断,混合煤可能形成以灌木为主和少量低等藻类输入的还原环境,光亮煤形成于弱氧化的森林沼泽,半亮煤形成于有大量蕨类植物输入的灌木和森林沼泽。

Samples of three different coal lithotypes i.e. brights, semidulls and cannel coal, are taken from the west open pit mine in Fushun coal field. The studies of petrology show that brights are rich in vitrinite and resinite, semidulls contain more than 20% inertinite and exetinite of cannel coal reaches up 7%. Cannel coal belongs to Ⅰ - Ⅱ type of kerogen, brights and semidulls are of Ⅲ type acco-ding to Van Krevelen diagram. Based on the above results, and the cell structure of macerals, it is suggested that cannel coal is formed by the shrub and some algae plant communities in relative anaerobic environments, and the bright coal is formed by the forest plant communities in relative aerobic environments, and semidull coal is formed by shrub or forest swamp containing lots of angiosperms.