VSP data and well log information from the Ross Lake oilfield, Saskatchewan (Husky Energy Inc.) are used to estimate P-wave and S-wave quality-factors. We used both vertical and horizontal vibrators as sources and a downhole three-component tool. From the spectral ratio method, results are obtained for QP as well as QS. We estimate an average QP, over an interval of 200-1200m, to be 67 from the spectral ratio technique, about 40 from drift curves, and 80 from convolutional model data matching. QS estimates over the same interval are 23 from the spectral ratio method and about 37 from "guesstimated" S-wave drift curves.
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