HR: 1330h
AN: H42B-1071    [PDF]
TI: Estimating Equivalent Continuum Scales in Fractured Aquifer Watersheds Using Discrete Feature Network Simulation
AU: * Wellman, T P
EM: tpwellma@mines.edu
AF: Colorado School Of Mines, 1516 Illinois St, Golden, CO 80401
AU: Poeter, E P
EM: epoeter@mines.edu
AF: Colorado School Of Mines, 1516 Illinois St, Golden, CO 80401
AB: Fractured aquifers serve as primary water resources throughout the western United States. In light of diminishing water supply, management practices must be improved to promote resource sustainability. Ground-water flow models are often the preferred management tool, but can be computationally expensive and difficult to implement in large-scale fractured environments. Discrete feature network (DFN) simulation is a robust approach for modeling fluid movement in fractured architecture, but numerically expensive for large-scale models. By using an equivalent continuum model (ECM) numerical expense may be substantially reduced. An intrinsic assumption of the ECM approach is that the geologic media is represented accurately as a continuum, requiring that grid scale discretization correspond to representative elementary scale (RES) at each location within a fractured aquifer. Heterogeneity and compartmentalization likely cause regions with large differences in fracture permeability and connectivity, resulting in spatially variable RES. Thus, while regional flow may be honored using essentially any grid pattern, failure to properly represent spatially variable RES could lead to erroneous predictions of local flow and transport, especially in highly heterogeneous zones. The purpose of our study is to determine whether head predictions from DFN flow simulations can delineate spatially variable RES in fractured aquifers. Provided there is a correlation of simulated hydraulic head to continuum scale, we hypothesize that RES can be identified using spatially disperse water level observations within a fractured aquifer watershed. Preliminary results suggest there is potential for using hydraulic head data to determine the RES. Ongoing research is necessary to confirm these preliminary results and our hypothesis.
DE: 1829 Groundwater hydrology
DE: 1884 Water supply
DE: 1894 Instruments and techniques
SC: Hydrology [H]
MN: 2003 Fall Meeting