青海木里矿区义海煤矿下1煤的煤相及古泥炭沼泽演化

煤相及相关地球化学特征,是指示古泥炭沼泽条件的重要标志。基于木里矿区义海煤矿下1煤层的显微组分特征、煤相和地球化学等测试分析结果,对该煤层的煤相及古泥炭沼泽演化开展精细研究。结果表明,下1煤层垂向显微组分含量构成5个演化旋回,对应煤相演化的5个阶段。时间序列上,下1煤层的沼泽水体的水介质条件呈现出波动式变化,且这种波动式变化与煤相阶段及煤岩组分垂向分段存在一定的吻合,第Ⅰ、Ⅱ阶段水动力条件经历了由弱变强的演化过程,第Ⅲ~Ⅴ阶段水动力条件由弱至强再减弱的演化趋势,阶段内部存在不同程度的波动变化。

Coal No.1 L Coal Facies and Paleo-peat Bog Evolution in Yihai Coalmine,Muri Mining Area,Qinghai

Coal facies and related geochemical features are important indicators to indicate paleo-peat bog conditions.Based on coal No.1 L maceral features,coal facies and geochemical tested and analyzed results in the Yihai coalmine,Muri mining area,have carried out detailed study on coal facies and paleo-peat bog evolution.The result has shown that coal No.1 L vertical maceral contents have consisted of 5 evolutional cycles,corresponding to 5 stages of coal facies evolution.On the time sequence,coal No.1 L bog water body aqueous medium condition presented undulating changes,thus a certain extent consistent with coal facies and coal lithotype vertical segmentation.During stages I and II,hydrodynamic condition has experienced from weak to strong evolutional process;during stages III^V from weak to strong then weakening evolutional trend;within each stage has existed varying degrees of undulating changes.