OASES - Ocean Acoustics and Seismic Exploration Synthesis

Description

OASES is a general purpose computer code for modeling seismo-acoustic propagation in horizontally stratified waveguides using wavenumber integration in combination with the Direct Global Matrix solution technique. It is basically an upgraded version of SAFARI. Compared to SAFARI version 3.0, which was once by NURC (formerly known as SACLANTCEN), OASES provides improved numerical efficiency, and the global matrix mapping has been re-defined to ensure unconditional numerical stability in the few extreme cases where the original SAFARI has proved unstable. OASES is downward compatible with SAFARI, and the preparation of input files follows the guidelines of the SAFARI manual. However, there are several new options, and OASES is shipped with it's own, self-contained, documentation.

Latest OASES Release: Version 3.1 - 28 Oct 2004

OASES News:

Version 2.2 of OAST can now optionally ('f') use a full Hankel Transform for the wavenumber integral. A New fast Hankel transform has been developed, allowing accurate nearfield computations at a computational cost insignificantly greater than the default FFP integration.
Version 2.1 and higher of OASES allow for stratifications including an arbitrary number of poro-elastic layers, with the propagation described by Biot's theory. This modification has been developed and incorporated into version 1.7 and 1.8 by Morrie Stern at the University of Texas at Austin, in collaboration with Nick Chotiros and Jim Tencate at ARL/UT, and distributed separately by Nick Chotiros. Their Biot algorithm has now been incorporated as a standard feature of the official OASES distribution.
Version 2.1 also handles propagation in stratified flow.
The full Version 2.x contains the new Range-Dependent OASES modules RDOAST and RDOASP.
User's Guide available on-line !!
PP can now generate trace files in MATLAB-5 format

How to get the OASES Package

The full version of OASES is available for licensing through the MIT Technology Licensing Office. The Licensing Officer is Daniel Dardani, Phone (617) 253-6966, Fax (617) 258-6790.

How to get the OASES Export Package

A limited, public domain Export Version of the OASES package is available via http. It can be accessed as a tar file in either gzipped (.tar.gz) or compressed (.tar.Z) form.

Click here for the gzipped form.
Click here for the compressed form.

How to Install OASES

Once you have transferred the tar file to your machine, you must first uncompress it:

> uncompress oases.tar.Z
or
> gunzip oases.tar.gz

You can get get a listing of the content by

> tar tf oases.tar

Now, move oases.export.tar to the root directory where you want the OASES directory tree to be placed, usually your HOME directory, and type

> tar xvf oases.tar

Now rename the directory to oases:

> mv oases_export oases

Now go into the oases directory

> cd oases

Here you will find the master make file 'Makefile'. If you are installing on a Sun-SPARC, a DEC AXP or Decstation, or an SGI, and you are happy with the default setup, then simply type:

> make all

and the whole OASES package will be compiled and linked into binaries placed in the directory $HOME/oases/bin.
Put the bin directory BIN you have chosen into your PATH, and move all the command files shipped in oases/bin to this directory as well.

If you are running under X-windows, answer x when MINDIS asks for the terminal type, or you may set the environmental variable in your .login file:

setenv USRTERMTYPE x

Type rehash, and you are ready to go. You will find sample data files in oases/tloss, oases/pulse, and oases/rcoef.

User Manual

The documentation for OASES is available as a supplement to the SAFARI manual either on-line or in LaTeX format in the oases/doc directory of the distribution. It is also available as a PDF or Postscript file

Good luck and have fun.

Henrik Schmidt

References

H. Schmidt and F.B. Jensen, Efficient numerical solution technique for wave propagation in horizontally stratified environments, Comp. & Maths. with Appls. 11:699-715, 1985.
H. Schmidt and F.B. Jensen, A full wave solution for propagation in multilayered viscoelastic media with application to Gaussian beam reflection at fluid-solid interfaces, J. Acoust. Soc. Am., 77:813-825, 1985.
H. Schmidt and J. Glattetre, A fast field model for three-dimensional wave propagation in stratified environments based on the global matrix method, J. Acoust. Soc. Am., 78:2105-2114, 1985.
H. Schmidt and G. Tango, Efficient global matrix approach to the computation of synthetic seismograms, Geophys. J. R. Astr. Soc., 84:331-359, 1986.
H. Schmidt, SAFARI: Seismo-acoustic fast field algorithm for range independent environments. User's Guide, SR 113, SACLANT ASW Research Centre, La Spezia, Italy, 1987.
H. Schmidt and W.A. Kuperman, Estimation of surface noise source level from low-frequency seismoacoustic ambient noise measurements, J. Acoust. Soc. Am., 84:2153-2162, 1988.
A.B. Baggeroer, W.A. Kuperman and H. Schmidt, Matched field processing: Source localization in correlated noise as an optimum parameter estimation problem, J. Acoust. Soc. Am., 83:571-587, 1988.
W.A. Kuperman and H. Schmidt, Self-consistent perturbation approach to rough surface scattering in stratified elastic media, J. Acoust. Soc. Am., 86:1511-1522, 1989.
J.S. Kim, Radiation from directional seismic sources in laterally stratified media with application to Arctic ice cracking noise, PhD thesis, Massachusetts Institute of Technology, May 1989.
H. Schmidt, A.B. Baggeroer, W.A. Kuperman and E.K. Scheer, Environmentally tolerant beamforming for high-resolution matched field processing: deterministic mismatch, J. Acoust. Soc. Am., 88:1851-1862, 1990.
F.B. Jensen, W.A. Kuperman, M.B. Porter, and H. Schmidt, Computational Ocean Acoustics, American Institute of Physics, New York, 1994.
H. Schmidt and W.A. Kuperman, Spectral and modal representations of the Doppler-shifted field in ocean waveguides, J. Acoust. Soc. Am., 96(1):386-395, 1994.
A.L. Kurkjian, R.T. Coates, J.E. White, and H. Schmidt, Finite-difference and frequency-wavenumber modeling of seismic monopole sources and receivers in fluid-filled boreholes, Geophysics, 59:1053-1064, 1994.
H. Schmidt and W.A. Kuperman, Spectral representations of rough interface reverberation in stratified ocean waveguides, J. Acoust. Soc. Am., 97:2199-2209, 1995.
H. Schmidt, W. Seong, and J. T. Goh, Spectral super-element approach to range-dependent ocean acoustic modeling, J. Acoust. Soc. Am., 98:465-472, 1995.
J.T. Goh and H. Schmidt, A hybrid coupled wave-number integration approach to range-dependent seismo-acoustic modeling, J. Acoust. Soc. Am., 100:1409-1420, 1996.

Henrik Schmidt / henrik@mit.edu