Nimmer, Robin E. and Osiensky, James L. and Binley, Andrew and Sprenke, Kenneth F. and Williams, Barbara C. (2007) Electrical resistivity imaging of conductive plume dilution in fractured rock. Hydrogeology Journal, 15 (5). pp. 877-890. ISSN 1431-2174Full text not available from this repository.
Electrical resistance tomography (ERT) was used to monitor a conductive plume dilution experiment that was conducted in fractured basalt in order to assess its applications in this type of fractured-rock environment. Tap water was injected into an injection well for 34 days to dilute a pre-existing potassium chloride (KCl) plume at a site in Idaho, USA. No further fluids were introduced artificially during a 62-day monitoring period. Both surface ERT and cross-borehole ERT were used to monitor dilution and displacement of the plume. A square grid of land-surface electrodes was used with the surface ERT. Three-dimensional images of surface ERT delineated areas of increased and decreased resistivities. Increasing resistivities are attributed to dilution/displacement of the KCl solution by tap-water invasion or the influx of seasonal recharge. Decreasing resistivities resulted from redistribution of residual KCl solution. Cross-borehole ERT was conducted between the injection well and each of seven surrounding monitoring wells. Polar plots of the injection-well resistivity data in the direction of each monitoring well delineate specific locations where tap water seeped from the injection well via preferential flow paths determined by time-dependent resistivity increases. Monitoring-well data indicate locations of clustered and isolated regions of resistivity changes.
|Journal or Publication Title:||Hydrogeology Journal|
|Uncontrolled Keywords:||Fractured rocks - Basalt - Tracer tests - Electrical resistance tomography - Plume|
|Subjects:||G Geography. Anthropology. Recreation > GE Environmental Sciences|
|Departments:||Faculty of Science and Technology > Lancaster Environment Centre|
|Deposited By:||Prof Andrew Binley|
|Deposited On:||27 Apr 2009 16:42|
|Last Modified:||26 Jul 2012 16:30|
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