ABSTRACT: Seismic Velocity Models for Heat Zones in Athabasca Tar Sands

L. R. Lines, J. D. Covey

Recent studies indicate that the acoustical velocity within Athabasca tar sands decreases as temperature increases due to steam injection. Time variant velocity models are derived form the seismic traveltime arrivals of both reflection and borehole data. The model's layer depths are established by using image-ray modeling of traveltimes prior to steam injection. The changes in velocity due to steam injection are modeled by using traveltime data from a monitor survey after steam injection. The velocity models are essentially determined by reflection traveltimes. The low-velocity zones show a good correlation with the zones of expected temperature increase at the injector well positions. The results indicate that velocity models obtained from seismic traveltimes may prove u eful in detecting steam fronts in tar sands.

AAPG Search and Discovery Article #91003©1990 AAPG Annual Convention, San Francisco, California, June 3-6, 1990