HR: 0800h
AN: H41B-0413    [Abstracts]
TI: An Integrated Geoelectric Assessment of Fracture and Anisotropy Characterization of the North New Jersey Highlands Bedrock
AU: * Wishart, D N
EM: debonnewishart@yahoo.com
AF: Rutgers University, Department of Earth and Environmental Sciences 101 Warren Street Smith Hall 141, Newark, NJ 07102 United States
AU: Slater, L D
EM: lslater@andromeda.rutgers.edu
AF: Rutgers University, Department of Earth and Environmental Sciences 101 Warren Street Smith Hall 141, Newark, NJ 07102 United States
AU: Bolden, A G
EM: boldren@pegasus.rutgers.edu
AF: Rutgers University, Department of Earth and Environmental Sciences 101 Warren Street Smith Hall 141, Newark, NJ 07102 United States
AB: The optimization of groundwater resources and aquifer management today demands a thorough understanding of the relationships between hydraulic and electric properties that are controlled by directional changes in the microgeometry of porous media (anisotropy). The quantification of anisotropy of fractured saturated media, containing both water and air are crucial for improving the capability to predict contaminant migration and groundwater transport in such media. The analogy between Darcy's Law and Ohm's Law for electric current flow makes it possible to relate hydraulic conductivity to electrical resistivity. Unfortunately, the resistivity measurement is not a unique proxy measure of a water bearing fracture as other features, particularly clay minerals, are also electrically conductive. Furthermore, electrical resistivity provides no information on flow characteristics. Traditional collinear electrode arrays (Wenner and Schlumberger) utilize the conventional azimuthal resistivity technique which is incapable of distinguishing subsurface anisotropy from inhomogeneity in subsurface media. Consequently, failures of the azimuthal resistivity method to adequately characterize fractures are reported and the method has not significantly advanced. In the North New Jersey Highlands, we integrate a type of pole-dipole electrode configuration, the arrow-type (AT) azimuthal resistivity, a non-linear array to distinguish anisotropy from inhomogeneity, induced polarization (IP) to determine surface electrical properties of the fractured subsurface, and self potential (SP) measurements to determine the general direction of groundwater flow through these fractures.
DE: 1832 Groundwater transport
DE: 1853 Precipitation-radar
DE: 5104 Fracture and flow
DE: 5109 Magnetic and electrical properties (0925)
DE: 5114 Permeability and porosity
SC: Hydrology [H]
MN: Fall Meeting 2005