HR: 13:55h
AN: H23I-02    [Abstracts]
TI: Analysis of Multiple-Aquifer Tests Using a Single Moving Radial Inverse Model
AU: * Yobbi, D K
EM: dyobbi@usgs.gov
AF: U.S. Geological Survey, 10500 University Center Dr. Suite 215, Tampa, FL 33612 United States
AB: Multiple aquifer tests in different aquifers are analyzed with a single, moving radial inverse numerical model that shifts between production wells for each stress period of a multiple aquifer test and is centered on the production well during each test. This analysis was applied at 10 sites in west-central Florida. Sites typically were designed with multiple production wells, one in each aquifer, and one or more observation wells in each aquifer. The analysis yields estimates of model parameters for the entire model using information from each test, but only one model, with one set of optimum parameters. Simulating multiple aquifer tests with a single model facilitates parameter estimation because the hydrogeologic column is defined with a single, internally consistent set of hydraulic properties. Simultaneous interpretation of entire hydrogeologic columns with inverse numerical models improved hydraulic property estimates. A single, consistent set of hydraulic property estimates resulted from all aquifer tests, instead of conflicting estimates from many independent analyses. Vertical hydraulic conductivity of confining units could be estimated with accuracies comparable to those of the horizontal hydraulic conductivity of aquifers. However, the uncertainty of specific storage of the confining units was not reduced commensurately. The most reliable estimates were obtained when drawdown was measured in adjacent permeable layers.
DE: 1828 Groundwater hydraulics
DE: 1847 Modeling
DE: 1849 Numerical approximations and analysis
SC: Hydrology [H]
MN: Fall Meeting 2005