The Colorado School of Mines is a small public teaching and research university devoted to engineering and applied science, with special expertise in the development and stewardship of the Earth's natural resources. Located in Golden, Colorado, CSM was ranked 29th, in America among national...
(CSM).
History
Einar Kjartansson began writing what is now called SU (the SY package) in the late 1970s while still a graduate student at Jon Claerbout's Stanford Exploration Project
Stanford Exploration Project
The Stanford Exploration Project is an industry-funded academic consortium within the Geophysics Department at Stanford University. SEP research has contributed greatly to improving the theory and practice of constructing 3-D and 4-D images of the earth from seismic echo soundings...
(SEP). He continued to expand the package while he was a professor at the University of Utah in the early eighties. In 1984, during an extended visit to SEP Einar introduced SY to Shuki Ronen, then a graduate student at Stanford. Ronen further developed SY from 1984 to 1986. Other students at SEP started to use it and contributed code and ideas. SY was inspired by much other software developed at SEP and benefited from the foundations laid by Claerbout and many of his students; Rob Clayton, Stew Levin, Dave Hale, Jeff
Thorson, Chuck Sword, and others who pioneered seismic processing on Unix in the seventies and early eighties.
The Colorado School of Mines is a small public teaching and research university devoted to engineering and applied science, with special expertise in the development and stewardship of the Earth's natural resources. Located in Golden, Colorado, CSM was ranked 29th, in America among national...
during his one year postdoctoral appointment there, Ronen aided Cohen in turning SU into a
supportable and exportable product.
Chris Liner (homepage), while a student at the Center, contributed to many of the graphics codes used in the pre-workstation (i.e, graphics terminal) age of SU. Liner continues to promote the use of SU in his students' research at the University of Houston
University of Houston
The University of Houston is a state research university, and is the flagship institution of the University of Houston System. Founded in 1927, it is Texas's third-largest university with nearly 40,000 students. Its campus spans 667 acres in southeast Houston, and was known as University of...
.
Craig Artley, now at Golden Geophysical, made major contributions to the graphics codes while still a student at CWP and continues to make significant contributions to the general package.
Dave Hale wrote several of the heavy lifting processing codes as well as most of the core scientific and graphics libraries.
John Stockwell's involvement with SU began in 1989. He was largely responsible for the Makefile in the package. He has been the main contact for the project since the first public release of SU in September 1992 (Release 17). After Jack Cohen's death in 1996, Stockwell assumed the role of principal investigator of the SU project and has since remained in that. The number of lines of code have more than tripled in the 11 years.
There have been many contributors to SU over the past two decades.
Syntax
The Seismic Unix routines run under the Unix terminal, and can get maximum efficiency when using it with Bourne Shell (sh) or Bourne-again Shell (bash) scripting techniques.
Simple routines
Many of the programs run simply by a command on the terminal, for instance, to visualize a seismogram, as wiggle traces
$ suxwigb < seismogram.su
or as an image plot
$ suximage < seismogram.su
More elaborated routines
It is also possible, to use bash features do elaborate more complex processing structures:
$ for ((i=1;i<=100;i++)); do
> sufdmod2 < model.bin > output.mov nx=200 nz=300 tmax=5 xs=$i zs=0 hsfile=seismogram.$i.su
> done
In the example above Seismic Unix will create 100 seismograms in 100 different source positions
SU Data
Here will have an explanation of how SU data is, it's headers and how they are organized in a big SU file with more than one gather:
--header—data—header—data--...
SU Programs
Seismic Unix has many of the processes needed on the geophysical processing. It is possible to use it to manipulate and create your own seismograms, and also to convert them between the SU standard file and the industry standard, the SEG Y
SEG Y
The SEG Y file format is one of several standards developed by the Society of Exploration Geophysicists for storing geophysical data. It is an open standard, and is controlled by the SEG Technical Standards Committee, a non-profit organization....
.
Here you can find a list of the programs that the SU package has, with a brief description and a link to its help page.
suquantile display some quantiles or ranks of a data set
surange get max and min values for non-zero header entries
sushw Set one or more Header Words using trace number, mod and integer divide to compute the header word values or input the header word values from a file
sutab print non zero header values and data for non-graphic terminals
sugain apply various types of gain to display traces
grm Generalized Reciprocal refraction analysis for a single layer
sumix compute weighted moving average (trace MIX) on a panel of seismic data
sumute mute above (or below) a user-defined polygonal curve with the distance along the curve specified by key header word
sunmo NMO for an arbitrary velocity function of time and CDP
supgc Programmed Gain Control--apply agc like function but the same function to all traces preserving relative amplitudes spatially
supws Phase stack or phase-weighted stack (PWS) of adjacent traces having the same key header word
suresstat Surface consistent source and receiver statics calculation
sustack stack adjacent traces having the same key header word
sustatic Elevation static corrections, apply corrections from headers or from a source and receiver statics file
sustaticrrs Elevation STATIC corrections, apply corrections from headers or from a source and receiver statics file, includes application of Residual Refraction Statics
suvibro Generates a Vibroseis sweep (linear, linear-segment, dB per octave, dB per hertz, T-power)
suvlength Adjust variable length traces to common length
SU community
Seismic Unix has a very large community, with lots of laboratories and researchers on the world using it. There's a listserver group where you can get help and post your questions about SU. To subscribe to it, click here.
You can also see the old posts that the users have already discussed, to do it click here
The Society of Exploration Geophysicists is a nonprofit organization dedicated to promoting the science of geophysics and the education of exploration geophysicists. The Society fosters the expert and ethical practice of geophysics in the exploration and development of natural resources, in...
Special Commendation
1994 - University to Industry award from the Colorado chapter of the Technology Transfer Society
The source of this article is wikipedia, the free encyclopedia. The text of this article is licensed under the GFDL.
