1. General Model Information

Name: moc3d - Three-dimensional method-of-characteristics ground-water

Acronym: MOC3D


Main medium: terrestrial
Main subject: biogeochemistry, hydrology
Organization level: ecosystem
Type of model: partial differential equations (finite differences,3D), ordinary differential equations
Main application:
Keywords: 3d, groundwater, solute transport, pollution, adsorption, ion-exchange, convection-dispersion equation, method of characteristics, MOC, finite difference numerics, first order degradation, nonlinear adsorption isotherms, confined aquifers

Contact:

U.S. Geological Survey
Hydrologic Analysis Software Support Team
R. Steven Regan
437 National Center
Reston, VA 20192
Phone:
Fax :
email: h2osoft@usgs.gov

Author(s):

Konikow, L.F., Goode, D.J., and Hornberger, G.Z.

Abstract:

New 3D-version of the widespread USGS-MOC model.

This model simulates three-dimensional solute transport in flowing ground water. The model computes changes in concentration of a single dissolved chemical constituent over time that are caused by advective transport, hydrodynamic dispersion (including both mech- anical dispersion and diffusion), mixing (or dilution) from fluid sources, and mathematically simple chemical reactions (including linear sorption, which is represented by a retardation factor, and decay).

METHOD

The transport model is integrated with MODFLOW, a three-dimensional ground-water flow model that uses implicit finite-difference methods to solve the transient flow equation. MOC3D uses the method-of- characteristics to solve the transport equation on the basis of the hydraulic gradients computed with MODFLOW for a given time step. Particle tracking is used to represent advective transport and explicit finite-difference methods are used to calculate the effects of other processes.

HISTORY

Version: 1.0 1996/11/08 - Initial release

DATA REQUIREMENTS:

Initial conditions, boundary conditions, aquifer properties at every node, and grid descriptors.


II. Technical Information

II.1 Executables:

Operating System(s): DOS - IBM-compatible PC, 386 or higher with math coprocessor, Data General AViiON DG/UX , Silicon Graphics Indigo, Sun SPARCstation Solaris USA: MOC3D software page Europe: MOC3D software page (DOS/DG/SGI/Sun) - Version: 1.0 last updated 1996/11/08

II.2 Source-code:

Programming Language(s): FORTRAN

II.3 Manuals:

User's Manual is available in Postscript and PDF Format, download from USA: MOC3D software page Europe: MOC3D software page

II.4 Data:



III. Mathematical Information


III.1 Mathematics


III.2 Quantities


III.2.1 Input

III.2.2 Output


IV. References

Konikow, L.F., Goode, D.J., and Hornberger, G.Z., 1996, A Three- Dimensional Method-of-Characteristics Solute-Transport Model (MOC3D): U.S. Geological Survey Water-Resources Investigations Report 96-4267, 87 p.

The basic MODFLOW documentation is contained in the following three reports:

McDonald, M.G., and Harbaugh, A.W., 1988, A modular three- imensional finite-difference ground-water flow model: U.S. Geological Survey Techniques of Water-Resources Investigations, book 6, chap. A1, 586 p.
Harbaugh, A.W., and McDonald, M.G., 1996, User's documentation for MODFLOW-96, and update to the U.S. Geological Survey modular finite-difference ground-water flow model: U.S. Geological Survey Open-File Report 96-485, 56 p.
Harbaugh, A.W., and McDonald, M.G., 1996, Programmer's documentation for MODFLOW-96, and update to the U.S. Geological Survey modular finite-difference ground-water flow model: U.S. Geological Survey Open-File Report 96-486, 220 p.

RELATED DOCUMENTATION:

Konikow, L.F., Granato, G.E., and Hornberger, G.Z., 1994, User's guide to revised method-of-characteristics solute-transport model (MOC--Version 3.1): U.S. Geological Survey Water-Resources Investigations Report 94-4115.
Goode, D.J., and Konikow, L.F., 1989 , Modification of a method-of- characteristics solute-transport model to incorporate decay and equilibrium-controlled sorption or ion exchange: U.S. Geological Survey Water-Resources Investigations Report 89-4030, 65 p.
Konikow, L.F., and Bredehoeft, J.D., 1978, Computer model of two- dimensional solute transport and dispersion in ground water: U.S. Geological Survey Techniques of Water-Resources Investigations, book 7, chap. C2, 90 p.


V. Further information in the World-Wide-Web


VI. Additional remarks


Last review of this document by: T. Gabele: 24. 6. 1997 -
Status of the document:
last modified by Tobias Gabele Wed Aug 21 21:44:45 CEST 2002

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