CWP/SU:Seismic Un*x   Release 40              10 April 2007
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Open source software for seismic research and seismic processing.
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You may download the codes from:
http://www.cwp.mines.edu/cwpcodes

You may join the listserver group at:
http://www.cwp.mines.edu/mailman/listinfo/seisunix
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3500+ installations verified by direct email,
10 to 20 downloads per day
525 members of the 
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I would like to express my gratitute to all of those who have contributed
to the Seismic Un*x project in the past year. Of particular note are
the efforts of Nils Maerklin of RISSC at the University of Napoli, and
of Reg Beardsley of Sugarland Texas.


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New License:
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In response to many discussions with open source software developers
and Seismic Un*x users, we have adopted a BSD style license, which
is contained in the file $CWPROOT/src/LEGAL_STATEMENT. The contents
of this file in its entirety are:

************* beginning of LEGAL_STATEMENT *********************************
This file is property of the Colorado School of Mines.

Copyright  2007, Colorado School of Mines,
All rights reserved.


Redistribution and use in source and binary forms, with or 
without modification, are permitted provided that the following 
conditions are met:

    *  Redistributions of source code must retain the above copyright 
       notice, this list of conditions and the following disclaimer.
    *  Redistributions in binary form must reproduce the above 
       copyright notice, this list of conditions and the following 
       disclaimer in the documentation and/or other materials provided 
       with the distribution.
    *  Neither the name of the Colorado School of Mines nor the names of
       its contributors may be used to endorse or promote products 
       derived from this software without specific prior written permission.

Warranty Disclaimer:
THIS SOFTWARE IS PROVIDED BY THE COLORADO SCHOOL OF MINES AND CONTRIBUTORS 
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 
COLORADO SCHOOL OF MINES OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 
STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
POSSIBILITY OF SUCH DAMAGE.


Export Restriction Disclaimer:
We believe that CWP/SU: Seismic Un*x is a low technology product that does
not appear on the Department of Commerce CCL list of restricted exports.
Accordingly, we believe that our product meets the qualifications of
an ECCN (export control classification number) of EAR99 and we believe
it fits the qualifications of NRR (no restrictions required), and
is thus not subject to export restrictions of any variety.

Approved Reference Format:
In publications, please refer to SU as per the following example:
Cohen, J. K. and Stockwell, Jr. J. W., (200_), CWP/SU: Seismic Un*x 
Release No. __: an open source software  package for seismic 
research and processing, 
Center for Wave Phenomena, Colorado School of Mines.

Articles about SU in peer-reviewed journals:
Saeki, T., (1999), A guide to Seismic Un*x (SU)(2)---examples of data processing (part 1), data input and preparation of headers, Butsuri-Tansa (Geophysical Exploration), vol. 52, no. 5, 465-477.
Stockwell, Jr. J. W. (1999), The CWP/SU: Seismic Un*x Package, Computers and Geosciences, May 1999.
Stockwell, Jr. J. W. (1997), Free Software in Education: A case study of CWP/SU: Seismic Un*x, The Leading Edge, July 1997.
Templeton, M. E., Gough, C.A., (1998), Web Seismic Un*x: Making seismic reflection processing more accessible, Computers and Geosciences.

Acknowledgements:
SU stands for CWP/SU:Seismic Un*x, a processing line developed at Colorado 
School of Mines, partially based on Stanford Exploration Project (SEP) 
software.
************* end of LEGAL_STATEMENT *********************************

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New collection of codes:  SLT/SU: Seismic Laboratory Tools (from Sugarland Texas)
This collection of codes is the work of many geophysicists, including
Zhiming Li, Rick Ottelini and others, most recently Reg Beardsley. 
Through the generosity of Chevron, these codes have been donated to 
the Colorado School of Mines and the Center for Wave Phenomena for 
general distribution in the hopes that it will prove useful to students i
and research scientists everywhere. 

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New Global changes:
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Apparently the places were memset was used to zero out arrays was
incorrect. All occurrences of 
memset( .., (int) '\0',...) 
where changed to memset( .., 0,..) 
as per suggestion of Marion Zhu and Reg Beardsley. 

The nature of the error is that the array might not be zeroed on some systems.
The error did not seem to show up on many systems, which is why it has not been 
detected until now.

Many codes throughout the SU package were affected.
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New header materials:
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The SU headers have *not* been changed, but the descriptions of these
header fields have been changed to align with SEGY REV 1, including
the descriptions of the SEGY "formats" and the values of "trid",
the trace id field.

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New codes include:
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par/main/randvel3d.c - add a random velocity layer to a 3D velocity profile
                       v(x,y,z)
		Thanks to: Chris Liner of ARAMCO
par/main/stiff2vel.c - convert stiffnesses to velocities. (The inverse of
		vel2stiff.)
		Thanks to: Chris Liner of ARAMCO
su/main/las2su.c - convert well log data in LAS format to SU format
		Thanks to: Werner Heigl of Apache and Chris Liner of ARAMCO
cwp/lib/waveforms.c - added Gaussian and Gaussian derivative waveforms
		Thanks to: Nils Maercklin of RISSC in Napoli
su/main/sualford.c - Alford Rotation
		Thanks to: Rodrigo Fuck of CWP
su/main/sucddecon.c  -  deconvolution by complex division in the 
                        frequency domain
		Thanks to: CWP: Ivan Vasconselos
su/main/sucountkey.c - count the number of unique values for a given keyword
		
su/main/sucentsamp.c - replace lobes on seismic data with spike of height
		scaled by the area of the lobe
		Thanks to: Providence Technologies: Tom Morgan
su/main/sumigtk2d.c - 2D time migration using the double square root operator
		Thanks to: Carlos Pacheco of CWP
su/main/surandspike.c - create a dataset of randomly distributed spikes
		Thanks to: Chris Liner of ARAMCO


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Changes to the codes include:
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su/main/suascii.c - a number of new formats added
		Thanks to: Nils Maercklin, RISSC, University of Napoli
su/main/suazimuth.c - options to calculate cmpx and cmpy coordinates 
		and several new azimuth formats added
		Thanks to: Nils Maercklin, RISSC, University of Napoli
su/main/suhrot.c - trid settings updated to make use of the new definitions
		of the trid parameters
		Change by John Stockwell of CWP
su/main/sunormalize.c - small fix to expand user inputs 
		Thanks to: Nils Maercklin, RISSC, University of Napoli
su/main/sumigfd.c - 
su/main/sumigffd.c - 
su/main/sumigps.c - 
su/main/sumigsplit.c - f1 and d1 header field values on output were not correct
		Fixed by John Stockwell

su/main/sumiggbzo.c - tracr header field values on output were not correct
		Fixed by John Stockwell

su/main/sumigprefd.c -
su/main/sumigpreffd.c -
su/main/sumigprepspi.c -
su/main/sumigpresp.c - All four of these codes were modified in the
		following ways. First, we replaced the goto-loop structures
                with do{ }while loops. Second, the values of sx,gx,sy,gy,
                and offset are now honored, and finally the traces are read
                in correctly. Additional comments in the selfdoc
		Changes by John Stockwell, inspired by requests and comments
                by CWP postdoc: Laxmidhar Behera

su/main/suea2df.c - a followup to removing the model building parts from
		the original code by Chris Julin. There were a number of
                bugs in the code, causing a skew in the output, also
		there were errors in the way the input was read.
		Thanks to: CWP: Steve Smith for motivating this, and to
                 comments from seisunix group participants.
su/main/suhistogram.c - additional parameter for a datum shift by keyword
		Thanks to: Reg Beardsley
su/main/sugain.c - added norm parameter to divide scale, as a complement
		to scale all by itself.
		Thanks to: Reg Beardsley
su/main/suop.c  - added an option to compute the RMS amplitude trace by trace.
		Inspired by a question from: Priyank Jaiswal of Rice University
su/main/sustack.c - repeat and nrepeat options to allow repetitions of
		stacked trace to appear in output file
		Thanks to: Werner Heigl of Apache
su/main/sustolt.c - changed nu to MAX(nu,nt) in call to stolt migration
                subroutine. This was preventing sustolt from being used
                in its advertised prestack migration role
		Bug report, thanks to: Chris Liner of ARAMCO
su/main/suresamp.c - small changes for well log support
		Thanks to: CENPET: Werner Heigl
su/main/suwaveform.c - create test waveforms
		Thanks to: Nils Maercklin, RISSC, University of Napoli

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My thanks to all of the users of SU for your thoughtful questions
and suggestions. 

			-John Stockwell   (10 April 2007)
		

John Stockwell	 | jstockwe@mines.edu
Center for Wave Phenomena (The Home of Seismic Un*x)
Colorado School of Mines
Golden, CO 80401 | http://www.cwp.mines.edu/cwpcodes
voice: (303) 273-3049

Our book:
Norman Bleistein, Jack K. Cohen, John W. Stockwell Jr., [2001],
Mathematics of multidimensional seismic imaging, migration, and inversion,
(Interdisciplinary Applied Mathematics, V. 13.), Springer-Verlag, New York.
