brot - BSU program to rotate 3-C seismic traces to a new coordinate system
brot [ -h | infile | itrx | itry | iopt | iangle ]
Basic Seismic Utilities (BSU) trace rotation program. This program was designed for use with 3-component Vertical Seismic Profile (VSP) data. The usual use is to rotate the two downhole horizontal component data into a new reference frame. For example, one might wish to align one component with a polarized source axis and the other horizontal component would become orthogonal to the source polarization axis. This program is designed to be used with the particular recording decisions made by the author (channels 1,2,3 downhole; vertical, "radial", "transverse"). A reference phone on the surface (channels 4,5,6; vertical, "radial", "transverse"). A typical survey around which this code was designed will have the reference phone be trace 5 aligned North, trace 6 aligned West, trace 4 vertical. The source axis will be aligned parallel to the trace 6 geophone. See author’s sign conventions, man page (polarity). Code is in Fortran 77.
Options
-h |
Online help giving details on command line arguments | ||
infile |
Input file name. | ||
itrx |
Trace number to associate with output x-axis. (This is usually the same as the transverse component on the reference phone) | ||
itry |
Trace number to associate with output y-axis. (This is usually the same as the radial component on the reference phone). | ||
iopt |
Rotation option. |
0=user supplied rotation angle
1=Transverse Allignment: trace 3 aligned to trace 6
(assumes azimuths in headers)
2=Radial Allignment: trace 2 aligned to trace 5
iangle |
User supplied rotation angle from x-axis |
NOTE:
If invoked with no options, will prompt user for input
parameters. Trace header angles are used with options iopt=1
or 2. These are limited to integer values (see bsegy).
EXAMPLE:
brot w001.seg 2 3 1
This will rotate the down-hole "radial", trace 2 to align with the surface reference phone "radial", trace 5. This assumes that the headers have encoded the azimuth for each geophone element (see bsegy, bhod, btor).
brotxxxx.seg
Output, rotated data. Named according to convention (first 4char brot, the next 4char are the first 4char of the input file name, suffix .seg)
standard output
produces a progress bar
brotxxxx.lst
Echo check of input parameters in listing file.
bhelp(1), bsegy(5), bhod(1), btor(1), polarity(5)
no known bugs
Copyright © 2017 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. <pm@cgiss.boisestate.edu>