I performed traveltime tomography on a 3-D seismic refraction dateset collected at Hill Air Force Base, Utah in 2000. The survey covers a 95m by 36m area over a contaminated aquifer that is bounded below by a clay aquiclude, in which a paleochannel acts as a trap for the contaminants.
Presented are results using an iterative, nonlinear, traveltime tomographic approach applied to 187,877 traveltimes. The resulting velocity model shows that the near-surface velocity increases by roughly a factor of 5 in the upper 15m, from about 300m/s to 1500m/s. Cross-sections through the model show a north-south trending low-velocity feature interpreted to be the channel structure. Checkerboard tests applied to the velocity model establishes a 7.5m lateral resolution throughout most of the depth range of interest. While the long wavelength features of the model reveal the paleo-channel, the velocity model is likely a broad and smooth characterization of the true velocity structure.
| Identifer | oai:union.ndltd.org:RICE/oai:scholarship.rice.edu:1911/17572 |
| Date | January 2003 |
| Creators | Azaria, Aron |
| Contributors | Zelt, Colin A. |
| Source Sets | Rice University |
| Language | English |
| Detected Language | English |
| Type | Thesis, Text |
| Format | 119 p., application/pdf |
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