Analysis of multicomponent seismic data recorded with a new hydraulic thumper source

Rafael J. Asuaje, Donald C. Lawton, Malcolm B. Bertram, Kevin L. Bertram, Kevin W. Hall, Eric V. Gallant

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.