Clay mineral assemblage and their implications in shihezi formation from the huaibei

摘要

Clay mineral assemblages in Shihezi Formation of Hualbei coal-bearing strata are de- termined by X-ray diffraction and Differential Thermal Analyzer, that is restated to the sediment faces and climatic changes in the source area, and to a lesser extent, alterations during burial di- agenesis. In the Upper Shihezi Formation, the clay fraction is dominated by kaolinite in northern part of the coal field, which was formed in alluvial sediment environment. But in the South of Huaibei coal field, the clay mineral assemblage consists of mainly illite that reflects the influence Of sea water.