INCORPORATING THE HYDRAULIC EFFECTS OF THE EPIKARST INTO MODFLOW-DCM, A KARST GROUNDWATER FLOW SIMULATOR

摘要

MODFLOW-DCM, a dual conductivity groundwater flow simulator, was developed to accommodate fast conduit flow embedded in a diffuse-flow matrix. Application of MODFLOW-DCM to regional-scale karst aquifers revealed a problem when attempting to match lag times between recharge (i.e., precipitation) events and aquifer responses exhibited by changes in groundwater elevation and spring discharge. The hydraulic effect of the epikarst layer has been identified as a potential source for the lag time. This study examines the hydraulic components attributed to the epikarst layer and our efforts to accommodate the hydraulics of the epikarst into MODFLOW-DCM.