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MODPATH: A Particle-Tracking Model for MODFLOW
MODPATH Version 6 Overview
MODPATH is a particle-tracking post-processing model that computes three-dimensional flow paths using output from groundwater-flow simulations based on MODFLOW, the U.S. Geological Survey (USGS) finite-difference groundwater flow model. The program uses a semianalytical particle-tracking scheme that allows an analytical expression of a particle's flow path to be obtained within each finite-difference grid cell. A particle's path is computed by tracking the particle from one cell to the next until it reaches a boundary, an internal sink/source, or satisfies another termination criterion.
Data input to MODPATH consists of a combination of MODFLOW input data files, MODFLOW head and flow output files, and other input files specific to MODPATH. Output from MODPATH consists of several output files, including a number of particle coordinate output files intended to serve as input data for other programs that process, analyze, and display the results in various ways.
MODPATH is written in FORTRAN and can be compiled by any FORTRAN compiler that fully supports FORTRAN-2003 or by most commercially available FORTRAN-95 compilers that support the major FORTRAN-2003 language extensions.
What's New in Version 6
MODPATH Version 6 is more efficient and easier to use than previous versions of MODPATH. The changes to MODPATH Version 6 also provide an improved code base for incorporating future changes. The major changes to MODPATH Version 6 include:
Information and Downloads: MODPATH v6.0.01, released August 24, 2012
Point of Contact
Support is provided for correcting bugs and clarification of how MODPATH is intended to work. Only limited assistance can be provided for applying MODPATH to specific problems by contacting the point of contact listed below:
Other USGS Groundwater Software
The USGS develops groundwater , water-quality, surface-water, and other water-resources software for use by the USGS in fulfilling its mission. Most of this software is available online for download at no charge.
Disclaimers and Notices
Please refer to the USGS Software User Rights Notice for complete use, copyright, and distribution information. The USGS provides no warranty, expressed or implied, as to the correctness of the furnished software or the suitability for any purpose. The software has been tested, but as with any complex software, there could be undetected errors. Users who find errors are requested to report them to the USGS.
References to non-USGS products, trade names, and (or) services are provided for information purposes only and do not constitute endorsement or warranty, express or implied, by the USGS, U.S. Department of Interior, or U.S. Government, as to their suitability, content, usefulness, functioning, completeness, or accuracy.
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