bvsp - BSU program which inverts first arrival times for a 2 layer velocity model (VSP recording)
bvsp [ -h | infile | itmax | zmin | zmax ]
Basic Seismic Utilities (BSU) for inverting first arrival times. The model is horizontal layers with parameters V1, V2, and V3 (velocities), Z1 and Z2 (layer thicknesses). The inversion assumes ray tracing is appropriate, and the algorithm traces direct, refracted direct, and interface (head) waves. The non-linear inversion adjusts the association of wave type dynamically as the inversion progresses. This program is intended for shallow (engineering) down-hole, vertical seismic profiles (VSP) surveys. First break picks are taken from the seismic headers (see bpic ) and picking can be done any number of ways, including manual picking within Seismic Unix (Colorado School of Mines) or with program bpic.
Options
|
-h |
Online help giving details on command line arguments | ||
|
infile |
Input file name | ||
|
itmax |
Number of iterations to perform in the non-linear inversion. | ||
|
zmin |
Minimum depth from which to take first arrival time picks. | ||
|
zmax |
Maximum depth from which to take first arrival time picks. |
NOTE:
If invoked with no options, will prompt user for input
parameters.
EXAMPLE:
bvsp twave.seg 20 0. 20.
First arrival time picks are extracted from twave.seg trace headers, and the inversion considers first arrival picks from 0 to 20 meters depth. Inversion limited to 20 iterations.
bvsp.gp
Gnuplot text file showing observed time pics (circles) and calculated time (solid line)
bvsp.ps
Postscript file showing observed time pics (circles) and calculated time (solid line)
bvspxxxx.m
Named according to convention
(first 4char bvsp, the next 4char are the first 4char of the
input file name, suffix .m) This is an Octave/Matlab
compatible script which can be used to plot the results of
the run. The Octave web page is
https://www.gnu.org/software/octave/
standard output
produces a progress bar
bvspxxxx.lst
echo check of input parameters and output listing in tabular format.
bhelp(1), bpic(1)
No known bugs
Copyright © 2024 by Paul Michaels
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
P. Michaels, PE. <[email protected]>