Travel-time computation

The ray-theory travel-times are computed for a vertical 2-D grid of 251*201 points. See the 3-D picture (21,5 kB) showing the positions of the source and gridpoints in the model. For coordinates of the point source and of the gridpoints refer to files 98-src.dat and 98-mtt.h. The elementary wave refracted at each interface is considered.

In the first step of the computation the system of rays creating ray tubes is traced running the program CRT. The data file 98-crt1.dat is used for specification of ray parameters.

The second step of the computation consists in interpolation within the ray tubes running the program MTT.

The computation and the visualization of the results is managed by the history file 98-mtt.h. Download all the necessary files and type "perl 98-mtt.h" from the command line to run the computation.

The computed multivalued travel-time maps may be sorted according to the arrival time (i.e. first arrival to the gridpoints, second arrival to the gridpoints, ...) using the program MGRD. The sorted singlevalued travel-time maps may be then visualized using program GRDPS:

The computed multivalued travel-time maps may be also sorted according to the ray histories using program MTTGRD, and then visualized using program GRDPS: