Direct Wave
In this example, we have 3 shot profiles, k004 is split spread. The minimum and maximum offset range for direct wave analysis is 0 to 30 meters. See Figure 13 to see how a cross-over distance is estimated. The command issued from a terminal is:
bref 008 3 0. 30. 1 0 k004.seg k008.seg k009.seg
The output files are:
- G008 system matrix columns: (shot, receiver, offset)
- D008 data vector, direct wave (arrival time,channel)
- E008 elevation vector, (trace number, station number, elevation)
Analysis requires program direct.m. Start an Octave session and type direct to start the program. Answer the GUI questions. The result and a file plot.ps will be output (see Figure 39).