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MODFLOW Ground-Water Model - User Guide to the Subsidence and Aquifer-System Compaction Package (SUB-WT) for Water-Table Aquifers

S. A. Leake·D. L. Galloway
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Abstract

A new computer program was developed to simulate vertical compaction in models of regional ground-water flow. The program simulates ground-water storage changes and compaction in discontinuous interbeds or in extensive confining units, accounting for stress-dependent changes in storage properties. The new program is a package for MODFLOW, the U.S. Geological Survey modular finite-difference ground-water flow model. Several features of the program make it useful for application in shallow, unconfined flow systems. Geostatic stress can be treated as a function of water-table elevation, and compaction is a function of computed changes in effective stress at the bottom of a model layer. Thickness of compressible sediments in an unconfined model layer can vary in proportion to saturated thickness.

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S. A. Leake, D. L. Galloway. 2007. MODFLOW Ground-Water Model - User Guide to the Subsidence and Aquifer-System Compaction Package (SUB-WT) for Water-Table Aquifers. https://doi.org/10.3133/tm6a23

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