genwav

NAME
SYNOPSIS
DESCRIPTION
FILES
NOTES
SEE ALSO
BUGS
COPYRIGHT
AUTHOR

NAME

genwav - Interactive program to generate namelist file for input into program waves

SYNOPSIS

genwav

DESCRIPTION

Compatible with Basic Seismic Utilities (BSU), this program genrates the namelist input file for program, waves , which computes Rayleigh wave dispersion curves in an elastic, 1-D layered earth. The program is interactive and prompts the user for an earth model, spectral limits, number of modes, and other signal processing requirements. Fortran 77 Version.

Example dialog
pm@penguin:~$
genwav

enter name of namelist file (40 char)
Example: waves.d
waves.d
enter name of dispersion curve file
(this is file from disper.f)
Example: earth.crv
earth.crv
enter near offset: xnear
1
enter group interval: delx
1
enter number of receivers: nrec
48
enter minimum group velocity expected
100
RECOMMENDED minimum tmax= 0.9600
enter: maximum trace time, tmax
2.0
enter: sample rate, fsamin
.001
enter frequencies: fmin, fmax
10,100
enter maximum mode to include
9
enter ksw switch 0=c plot, 1=k plot
0
enter type of plot format, mapmat
0=scilab 1=maple
0
enter Output option 0=Vertical 1=Radial
0
enter source depth
0
enter (3) diagonal elements, moment tensor
0,0,1
Padded Radix 2 tmax= 4.0960
Number of points in signal= 4096
--------------------------------------------------
.......Frequency interval= 0.24414061
NOTE: Frequency Interval MUST MATCH DISPER OUTPUT
WAVES will output signal length = 1.0/delf
IF MISMATCHED: CHANGE sample rate in WAVES
or RERUN DISPER
--------------------------------------------------
Number of frequencies= 409
output in =====>waves.d

File waves.d would then be processed by waves .

FILES

waves.d (or any other name you choose, first input)

This file will have the namelist content needed for waves .

Example Output

The following is a listing of the waves.d file contents generated by the above dialog.

waves.d

&waves
ksw= 0, stepz=20,
modes=1,2,3,4,5,6,7,8,9,
fmin= 10.0000, fmax= 100.0000,
fsamin= 0.00100,
curve=’earth.crv’,
mapmat=0,
matlb1=’maplec’, scilb1=’matc.sci’,
matlb2=’mapleu’, scilb2=’matu.sci’,
irvsel=0,
ofile=’waves.tmp’, /
&source
tm= 0.0, 0.0, 0.0,
0.0, 0.0, 0.0,
0.0, 0.0, 1.0,
sz= 0.00, sy=0.00, sx=0.00, /
&recvr
nrec=48,
rz=0.0,
ry=0.0,
rx=
1.000, 2.000, 3.000, 4.000, 5.000,
6.000, 7.000, 8.000, 9.000, 10.000,
11.000, 12.000, 13.000, 14.000, 15.000,
16.000, 17.000, 18.000, 19.000, 20.000,
21.000, 22.000, 23.000, 24.000, 25.000,
26.000, 27.000, 28.000, 29.000, 30.000,
31.000, 32.000, 33.000, 34.000, 35.000,
36.000, 37.000, 38.000, 39.000, 40.000,
41.000, 42.000, 43.000, 44.000, 45.000,
46.000, 47.000, 48.000,
/

NOTES

name of dispersion curve file

This is the output file name from the disper run.

xnear

This is the near offset distance in meters for first geophone. All geophones are placed at depth=0 by default (change rz=0.0 if at depth).

delx

This is the constant geophone spacing in meters.

nrec

This is the number of geophones (receivers) for the synthetic seismogram. An array of rx= values are generated from the above choices for near offset and geophone spacing.

minimum group velocity expected

This is used to estimate a minimum maximum time to avoid Fourier Transform wrap around. The program then gives an estimate to use.

tmax

The maximum time (in seconds) for synthetic seismogram traces (synthetic seismograms computed by program waves).

sample rate

This is actually the sample interval in seconds. This establishes the frequency interval consistent with the intended aperture in the case where the wave output will be used to compute synthetic Rayleigh wave seismograms in bsegy format.

frequency minimum and maximum

These are given in Hz. Recommend using more bandwidth than you are interested in. Too little bandwidth will produce a very ringy synthetic seismogram. You can always filter the synthetic back later.

maximum mode #

Phase velocities will be computed for modes 1 through maximum_mode. Hard-wired limit is 9 modes.

ksw switch

This controls type of dispersion plot, by phase velocity or wavenumber.

plot format

This chooses the type of output file for plots, Scilab or Maple.

output option

Choose either Vertical or Horizontal particle motion for output. Output files named wavV.seg or wavR.seg respectively. The variable irvsel=0 chooses vertical component geophones, and irvsel=1 selects radial, in-line horizontal geophones.

source depth

The depth of the simulated source.

3 diagonal elements of moment tensor

For an explosive source, 1,1,1. The elements are t11,t22,t33 (horiz-x,horiz-y,vertical). You can edit the waves.d file to fill in other possible source types, like double couple. For a vertical impact source, 0,0,1 would be entered.

SEE ALSO

disper(1), gendis(1), waves(1), showmdl(1), halfsp(1)

BUGS

no known bugs

COPYRIGHT

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.

AUTHOR

P. Michaels, PE. <paulmichaels@.boisestate.edu>