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by Jian-Li Song and Uri ten Brink
U.S. Geological
Survey, Woods Hole, MA 02543
2004
RayGUI 2.0, a new version of RayGUI, a graphical user interface (GUI) to the seismic travel-time modeling program of Zelt and Smith (1992), has been released. RayGUI 2.0 represents a significant improvement over the previous version of RayGUI (RayGUI 1.04; Loss and others, 1998a, b). RayGUI 2.0 uses an updated Java version (1.3), and it can run on various operating systems (UNIX, Linux, and Mac OS X). Several new functions have been incorporated, including: execute the forward and inversion codes of Zelt and Smith (1992), create models or add new parts of models from an ASCII file, graphically add layers or points, graphically pinch layers, change the velocity value of a control point, report point location and velocity, import traveltime lists, generate postscript files, export the velocity model into an ASCII file, generate 1D velocity profiles at specified locations, calculate root-mean-square errors between observed and calculated arrivals for selected phases, access the ray trace log, and several other new display features.
Ray-tracing in RayGUI is performed by invoking rayinvr, a widely-used package for a 2-D forward modeling and inversion of seismic rays in an isotropic medium (Zelt and Smith, 1992). RayGUI2.0 completely integrates all the functionalities of the rayinvr program, and the user does not need to run rayinvr separately. The velocity model consists of distinct layers with continuous 2D velocity gradients, with vertically and laterally varying velocities. Layer interfaces and velocities are defined by control points, which the user specifies. Observed and calculated traveltimes can be displayed either in the same window as the velocity model or in a separate window. Users can interactively select a portion of the velocity model to display by dragging a rectangle over the velocity model, and specify time and distance ranges of the displayed plots by entering ranges in separate windows. RayGUI 2.0 enables the user to graphically edit a velocity model, to select ray type, to select shot and to change the ray-tracing parameters.
RayGUI 2.0 can be used by multiple users simultaneously as long as each user is working in a distinct working directory. Users of previous versions or RayGUI were prevented from modeling multiple arrivals from multiple shots due to a computational speed limitation. This is no longer an issue, as RayGUI 2.0 is computationally efficient.
RayGUI 2.0 was written in JAVA, and FORTRAN 77 and ANSI-C compliers are required
to compile rayinvr and some auxiliary programs. The package can be freely
obtained for non-commercial purposes by contacting Dr. Uri ten Brink at utenbrink@usgs.gov.
More details and the complete manual can be downloaded following the link below:
USGS Open-File Report 2004-1426
(PDF format).
Loss, J., ten Brink, U. and Pecher, I., 1998a, RayGUI - a graphical 2-D ray-tracing interface for UNIX: EOS, v. 79, no. 28, p. 334.
Loss, J., Pecher, I. and ten Brink, U., 1998b, RayGUI - a graphical 2-D ray-tracing package for UNIX: U.S. Geological Survey Open-File Report 98-203.
Zelt, C. A. and Smith, R.B., 1992, Seismic traveltime inversion for 2-D crustal velocity structure: Geophysical Journal International, v. 108, p. 16-34.
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