广西煤的常量元素地球化学特征

INVARIABLE ELEMENT GEOCHEMISTRY OF COALS IN GUANGXI

系统分析了广西未变质煤、区域变质煤和热液变质煤的ＳｉＯ２、Ａｌ２Ｏ３、Ｆｅ２Ｏ３、ＭｇＯ、ＣａＯ、Ｎａ２Ｏ、Ｋ２Ｏ、ＴｉＯ２、ＳＯ３。低灰分煤的常量元素主要来自古植物对成土母岩的选择性吸收，具明显的超基性或基性特征。随煤变质程度升高，未变质煤、区域变质煤中的常量元素没有发生迁移，而热液变质煤中的ＳｉＯ２和Ａｌ２Ｏ３相对增加，ＳＯ３和ＣａＯ相对减少。

We have systematically analysed SiO 2,Al 2O 3,Fe 2O 3,MgO,CaO,Na 2O,K 2O,TiO 2 and SO 3 in the unmetamorphosed, regionally metamorphosed and hydrothermally metamorphosed coals in Guangxi. The invariable elements of low-ash coals are mostly attributed to the selective absorption during the growth of fossil plants. Their coal ashes are characteristic of ultrabasic or basic rocks. As coal ranks increase, the invariable elements in the unmetamorphosed and regionally metamorphosed coals will not migrate, however, SiO 2 and Al 2O 3 will increaes as well as SO 3 and CaO will decrease relatively in the hydro thermally metancorphosed coals.