GeoTom, LLC software

GeoTomCG can process and display 2-D and 3-D crosshole or VSP seismic or radar data. The display below shows calculated seismic velocities from a dam in Taiwan being investigated for earthquake damage¹. S and R indicate source and receiver positions, respectively. The crosshatch pattern indicates areas with few raypaths. The investigators reported that the seismic velocities were consistent with results obtained by other geophysical methods.

Display features. The display below shows traces 34 to 51 from a 146-trace seismograph file. Red squares are auto-picks. Blue dots and arrows are final picks, which usually can be left at the auto-pick positions with good data. Green and blue-green amplitude dots (hard to see in this display) are on the three peaks following the time pick. Trace 35 was labeled dead, so the time is 0. The magnified display in the small box (trace 45) allows more accurate examination of auto-picks and manual repicking, if necessary.

GeoTom has many years of experience processing clients’ tomographic data. GeoTom’s experience and the familiarity with the software provide efficient and reliable data processing. Clients can either provide seismograph files for use in picking traveltimes (or amplitudes) which are then used in tomographic calculations of velocity (or attenuation) or provide traveltimes (or amplitudes) picked by the client which are used in the tomographic calculations. The report of results can be informal, just providing results, or GeoTom can provide a more formal report.