Vertical Seismic Profiling Experiment to Determine Depth and Dip of the Paleozoic Surface at Drill Hole U10bd, Nevada Test Site, Nevada

摘要

A vertical seismic profile experiment in drill hole UE10bd during September 1978 at the Nevada Test Site, Nevada was conducted. The purposes of the experiment were to obtain seismic reflections from the Paleozoic surface beneath the Quaternary and Tertiary deposits of Yucca Flat, and to compare different sources used to generate seismic energy for vertical seismic profiles. Five profiles were made, two using different surface sources and three using different downhole sources. The seismic signal was detected with a downhole clamping geophone. The reflection from the Paleozoic surface was evident on all five profiles, with no source showing a comparative advantage over the others. Velocity filtering was shown to be an extremely valuable tool for enhancing the reflection from the Paleozoic surface. The vertical seismic profiles suggest that seismic energy trapped in the near-surface zone is probably the reason for the limited success of previous attempts to map the Paleozoic surface with surface seismic-reflection surveys. Vertical seismic profiling was shown to be a viable method for obtaining reflections from the Paleozoic surface beneath Yucca Flat. (ERA citation 06:001429)