Contents of the gogeom script.

The topcon man page and online documentation will be useful in understanding the first command. What it does is combine the survey information from line3.nez with header information from the Bison file, bnk00010 to form a file, bnk00010.xyz which can be read by program bhed. The program bis2seg converts the Bison file to a BSEGY file with minimal headers, then bhed is run and merges the bnk0010.xyz information into the headers to complete the geometry setting. The Unix move command, “mv” , is used in places to rename the file to the 4 character BSEGY convention. The flow is replicated for shot 11. The gogeom script is as follows:

{listgogeom}
#!/bin/sh
# convert Bison to BSEGY
# shot10 (at station 24 line 1) Hammer Source
 topcon line3.nez bnk00010 0003 0. 24 48 1 48 10 0. 0  180  0  0
 bis2seg bnk00010
 mv bnk00010.seg k010.seg
 bhed k010.seg bnk00010.xyz 0
 mv bhedk010.seg k010.seg

# shot11 (at station 1 line 1) Hammer Source
 topcon line3.nez bnk00011 0003 0. 1 48 1 48 11 0. 0  180  0  0
 bis2seg bnk00011
 mv bnk00011.seg k011.seg
 bhed k011.seg bnk00011.xyz 0
 mv bhedk011.seg k011.seg

listgogeom

After running gogeom, you will have files k010.seg and k011.seg in the bison directory. Move these to the /ID-102/seg directory, and change to that directory for the next step in the process. Figure 35 is a plot of the k011.seg data. The data have been scaled by program bscl, and then plotted with Seismic Unix, clip=1.

Figure 35: Scaled k011.seg refraction data

By the way, for those who don't have Bison formatted data, there is an alternative program in BSU named topcon2. It does essentially the same thing as topcon, but for SEG-2 formatted seismograph files. You will need to read the man pages on topcon2, since there are some differences.