Seismic Unix Scripts

Seismic Unix (SU) is a public domain seismic processing software package
written and maintained by the Center for Wave Phenomena at the Colorado
School of Mines in Golden, Colorado.  The current web site for SU is
http://www.cwp.mines.edu/cwpcodes.  SU is compatible with both UNIX and
LINUX operating systems.  The SU scripts provided on this disc and listed
below were modified from scripts written by the USGS Seafloor Mapping
Group in Woods Hole, Massachusetts, and run on a LINUX workstation.  These
SU scripts and other needed files are located in the tar file boom.tar,
which can be found within the SU subfolder of the SOFTWARE folder located
at the top level of this disc. These scripts are provided as examples
only. They may need to be modified to run on another system.  They also
require the use of several shareware programs such as ImageMagick and
Ghostscript. 

The example SU scripts provided here will allow the user to strip off 
navigation fixes from the SEG-Y headers, along with a fix for every 500 
shots, and produce a filtered and gained GIF image of each profile. These
images can then be displayed using a variety of shareware programs such as ImageMagick (Unix, Linux) or a web browser.

To use the scripts provided here you must first install SU on a UNIX or
LINUX system.  The scripts require that the following 4 subdirectories
(all at the same hierarchical level) be created before the scripts are
run: 1. nav, 2. segy, 3. seisimag, and 4. SU.  If you untar the boom.tar
file these subdirectories will be created for you.  The SU scripts and all
associated files (see below) should be located in the SU subdirectory. You
may put the SEG-Y files in the segy subdirectory.  The GIF images will be
written to the seisimag subdirectory and the navigation data to the nav
subdirectory.

Provided below is a step by step explanation of the processing sequence
and example parameters required by each script.  For more information
please refer to the SU documentation also provided on the web or on-line
if Seismic Unix is installed on the computer.  These scripts are provided
as examples only.  There are many differences in versions of UNIX and
LINUX. We developed these scripts to run on Red Hat LINUX 7.3.

Step 1.  Untar the boom.tar file (i.e. tar xvf boom.tar), and it will
create the 4 subdirectories and write the scripts and associated files to
the SU and nav subdirectories.

Step 2.  Make sure the permissions for all files in the SU subdirectory
have been set to allow execution (i.e. chmod +x scriptname).  These first
2 steps do not need to be repeated.

Step 3.  Run newcdutm. (Note: For data collected in lat/longs, use llnew
instead of newcdutm.) This script wants the following information, in this
order, on one line, separated by spaces: 
1= the directory location of the SEG-Y file (can be absolute or relative
path)
2= the filename without the .TRA extension
3= the output directory  (without the /SU, i.e. ..)

example: newcdutm ../segy 01b001 ..

Step 4.  Run boom.  This script wants the following information, in this
order, on one line, separated by spaces:
1= tmin (time minimum for this data set is 0)
2= tmax (time maximum, in milliseconds, i.e. .100)
3= directory location of the SU-formatted data (without the /SU)
4= the SU file name (without the .su extension)
5= the height of the plot in inches (try 8)
6= the pclip value (try 95 - higher is lighter, lower is darker)

example:  boom 0 .100 .. 01b001 8 95

Repeat steps 3 and 4 for each data file.

Step 5.  View the seismic profile written to the seisimag subdirectory
using a web browser or ImageMagick for GIF files or Ghostview for 
Postscript files.

The following list of files are produced or called by the SU scripts
(newcdutm and boom). These will also be extracted from the boom.tar file
and placed in the SU subdirectory:

boom- a script used to filter, gain, and display the SU formatted trace
data into Postscript and GIF image files

gsgifscript- needed by makegif to convert the Postscript image to GIF
format

history - records a record of the data processed and parameters used

landscape.ps- converts the Postscript plot to a landscape display
direction

llnew- script used to extract latitude and longitude values from the SEG-Y
headers and convert the data to SU format. (If data was collected with
lat/longs, substitute llnew for newcdutm in the examples above.)

makegif- converts the Postscript image to a GIF image

newcdutm- script used to extract UTM location data from the SEG-Y headers
and convert the SEG-Y formatted trace data to SU format

Note:  These are c-shell scripts.  Make sure that your .cshrc file has
been modified as per the SU installation instructions.  For example, on
our system you must add the location of /opt/cwp/bin to the set path
statement.  Also, a setenv statement must read setenv CWPROOT/opt/cwp.