NAME
point2 - An analytical solution for two-dimensional ground-water
solute transport in an infinite system with uniform flow
and a continuous point source
ABSTRACT
The program POINT2 computes the analytical solution to the two-
dimensional solute-transport equation for an infinite system with a
continuous point source.
METHOD
The computer program calculates the concentration for the two-
dimensional system based on the equation given in Wexler (1992a, p.
27). The concentration can be calculated for different times and
spatial locations.
HISTORY
Version 1.1 1996/04/03 - Code restructuring and clean up: use of
consistent spacing; use of upper and lower case variable names;
statement labels renumbered; comment statements altered to be
consistent; use of Hollerinth data in FORMAT statements removed;
all variables and routines declared; duplicate code placed in new
routines; interactive prompting for graphics output devices
added. Bug fixed in contour routine related to contours at the
left edge of the plot.
Version 1.0 1990/04/03 - Initial published version.
DATA REQUIREMENTS
The program requires data on advective velocity, dispersion
coefficient, spatial information, temporal information, and boundary
concentrations. Optional data may include a first-order solute-
decay coefficient.
OUTPUT OPTIONS
Output is the calculated concentrations at specified points in time
and space. A plotting option exists to view the output as graphs.
SYSTEM REQUIREMENTS
pgm_name is written in Fortran 77 with the following extensions:
use of include files and reference to compiler-dependent system date
and time routines. The program requires the file glq.pts
(provided), which contains normalized roots and weights of the
Legendre polynomials. A script program is provided to facilitate
connection of the program with the glq.pts file. Graphics are coded
using Computer Associates' DISSPLA library references. Generally,
the program is easily installed on most computer systems that have
access to the DISSPLA graphics library. Alternatively, graphics can
be disabled and data can be easily extracted from the program output
and plotted using graphic presentation programs. The code has been
used on UNIX-based computers.
DOCUMENTATION
Wexler, E.J., 1992a, Analytical solutions for one-, two-, and three-
dimensional solute transport in ground-water systems with uniform
flow: U.S. Geological Survey Techniques of Water-Resources
Investigations, book 3, chap. B7, 190 p.
Wexler, E.J., 1992b, Analytical solutions for one-, two-, and three-
dimensional solute transport in ground-water systems with uniform
flow -- Supplemental Report: Source codes for computer programs
and sample data sets: U.S. Geological Survey Open-File Report
92-78, 3 p., 1 computer diskette.
TRAINING
Some of the programs are introduced in the class Ground-Water
Solute-Transport Concepts for Field Investigations (GW2005TC),
offered annually at the USGS National Training Center.
CONTACTS
Operation:
U.S. Geological Survey
Office of Ground Water
Thomas E. Reilly
411 National Center
Reston, VA 20192
tereilly@usgs.gov
Distribution:
U.S. Geological Survey
Hydrologic Analysis Software Support Program
437 National Center
Reston, VA 20192
h2osoft@usgs.gov
Official versions of U.S. Geological Survey water-resources analysis
software are available for electronic retrieval via the World Wide
Web (WWW) at:
http://water.usgs.gov/software/
and via anonymous File Transfer Protocol (FTP) from:
water.usgs.gov (path: /pub/software).
The WWW page and anonymous FTP directory from which the ANALGWST
software can be retrieved are, respectively:
http://water.usgs.gov/software/analgwst.html
--and--
/pub/software/ground_water/analgwst