Since the shot and receiver locations are in the BSEGY headers, we can use program bcad to build a basemap by extracting this information and generating a CAD data exchange format file, *.dxf. For example,
bcad k008.seg 1 1 2.0
creates file bcadk008.dxf
. It is a simple “point” file with 2.0 meter labels.
All three recording files use the same geophone stations in this example, so the only
difference in running bcad on the 3 files will be the source location. If you
download the open source program,
dxf2fig, you can convert the *.dxf files to xfig format files.
These can then be edited in xfig to build a base map. I downloaded dxf2fig
from
http://homepage.usask.ca/~ijm451/fig/. (version 2.13). There are other versions at other websites, use a search engine if the location changes after this writing. I have included an edited version based on the two files k008.seg
and k009.seg
. the map is shown in Figure 27. Alternatively,
I recommend Qcad to work with *.dxf files directly. Qcad is available from
https://qcad.org/en/.