Relative Impermeability of the Ordovician Top and Risk Assessment of Water Inrush from Coal Floor in Baode Coalfield

Abstract

In order to study the safety mining of the deep buried coal seams being threatened by high pressure karst water, relative impermeability of the Ordovician top is demonstrated through studying lithology，filling degree of the karst fissures as well as wash water quantity, in the Baode mine field. Furthermore, the main influencing factors on impermeability of coal seam floor are analyzed, and divisional risk assessment of floor water-inrush from the Ordovician karst aquifer is performed. Overall，by considering the relative impermeable strata in the Ordovician top, the accuracy of risk assessment on coal floor water-inrush can be improved.