However, the current research studies on the mechanism of fault-delayed water inrush mainly focus on factors such as fault dip angle, aquifuge
thickness, and the damage of floor strata [36, 37], whereas fewer research studies consider filling media and filling structures in the fault .
where K and K' are the permeability coefficients of the aquifer and the aquifuge
, respectively; P and I are the water pressure and the hydraulic gradient, respectively; and L and w are the seepage length and the section area, respectively.
Bai, Seepage Characteristics of Top Stratum of Ordovician System and Its Application Study as Key Aquifuge
, China University of Mining & Technology, Xuzhou, China, 2008.