Development Mechanism And Control Factors Of Ordovician Carbonate Karst In Feicheng Coalfield

In North-China-Type coalfields,the main water source that threat coal exploitation of Taiyuan formation is ordovician karst water, Depth study of distribution about Ordovician limestone karst and its evolution has important theoretical significance, and it has practical guidance in prevention and treatment of mine water of deep coal seams in Feicheng coalfield and North-China-Type coalfields.This paper works over the geology theory,by methods of theoretical analysis,experiments and field measurement, through analysis of mine discharge,water inrush,karst collapse column and geophysical exploration datas, indirectly study the transverse characteristics and rules of ordovician karst on macroscopic; through test about rock slides and X-ray diffraction experiment, directly study the longitudinal characteristics and rules of ordovician karst on microscopic; through deeply study of devepment characteristics and rules,chemical composition and mineral portfolio of ordovician limestone,influence factors and evolution mechanism of ordovician karst in Feicheng coalfield. We obtain that the main mineral component of ordovices limestone is CaCO3 and the submember is CaMg(CO3)2·In pars superficialis the mainly karst form is cranny and in deep part the mainly karst form is groundwater flow. the main horizon Karst develop distance the top of ordovician limestone 50 meters.The development of karst under the control of structure.in the north part the main direction is NE,the middle part is NW,and the Eastern part is NNE. This paper Summarized the main influencing factors about karst, Mainly has chemical element factor,structure factor of carbonate,geological structure factors,groundwater factor and geographical factor. Summarized four period of the evolution about karst in Ficheng coalfield—late of Jurassic Period,Tertiary Period,Quaternary Period and Modern Times.