This paper examines the performance of the new multicomponent weight drop source built by CREWES. The source was tested on the University of Calgary campus to generate P-waves and S-waves, and to provide a detailed velocity structure of the near-surface. The source generates SH-waves by orienting the source mast +/-45 degrees from the vertical and subtracting records generated with opposite source polarities. This cancels P-waves and constructively adds SH waves.
The data collected show that the uppermost layer of the shallow subsurface has a P-wave velocity of 840 m/s and a SH-velocity of 215 m/s, yielding Vp/Vs of 3.90.
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