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MODFLOW-2000, The U.S. Geological Survey modular ground-water model: User guide to modularization concepts and the ground-water flow process

Arlen W. Harbaugh·Edward R. Banta·Mary C. Hill·Michael G. McDonald
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Abstract

MODFLOW is a computer program that numerically solves the three-dimensional ground-water flow equation for a porous medium by using a finite-difference method. Although MODFLOW was designed to be easily enhanced, the design was oriented toward additions to the ground-water flow equation. Frequently there is a need to solve additional equations; for example, transport equations and equations for estimating parameter values that produce the closest match between model-calculated heads and flows and measured values. This report documents a new version of MODFLOW, called MODFLOW-2000, which is designed to accommodate the solution of equations in addition to the ground-water flow equation. This report is a user's manual. It contains an overview of the old and added design concepts, documents one new package, and contains input instructions for using the model to solve the ground-water flow equation.

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Arlen W. Harbaugh, Edward R. Banta, Mary C. Hill, Michael G. McDonald. 2000. MODFLOW-2000, The U.S. Geological Survey modular ground-water model: User guide to modularization concepts and the ground-water flow process. https://doi.org/10.3133/ofr200092

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