Multiple tests for identifying hydraulic conductivities of south and north boundary faults at Ganhe field, Huozhou Coal Electricity Group Co., Ltd, China

Abstract

Hydraulic conductivities of faults influence the mining design and safety of a coalmine badly. Results of field and indoor tests on hydraulic conductivities of the boundary faults in Ganhe coalfield in China are illustrated. According to the drilling engineering, Xiatuanbai fault and F1 fault near north boundary and Xiazhangduan fault near south boundary are all transtensional normal faults. Furthermore, there formed obvious fracture zones in the Ordovician strata of both sides of the faults with respect to its influence and their water conductivities are all obvious. Results of the pumping test show there are obvious hydraulic connectivities between Fengfeng Formation aquifers and Upper Majiagou Formation aquifers on both sides of the three boundary faults. Therefore, they are all partial water-conductive faults. Results of connectivity tests also show there are obvious hydraulic connectivities in the karst aquifers on both sides of Xiatuanbai fault and Xiazhangduan fault and they are both partial conductive faults. Finally, differences on hydrochemical and stable isotope features between both sides of the three faults are all inconspicuous and the same results on the hydraulic conductivities of the three faults are obtained. The above comprehensive conclusions provide a strong basis for water disaster control of Ganhe mine.