Multicomponent Seismic Data Interpretation

Susan L. M. Miller

A procedure is developed for the coupled interpretation of multicomponent (P-P and P-S) seismic data, and is illustrated using two 3C-2D seismic datasets from Alberta, Canada. In both cases, numerical modelling studies were used to assist the interpretation. The principal objective of the Lousana survey was to differentiate reservoir dolomite from tight anhydrite within the Nisku Formation using seismic methods. Vp/Vs analysis of two intervals which contained the target mapped a decrease in Vp/Vs coincident with productive wells. The second survey, from the Blackfoot Field, targeted incised-valley sandstones in the Lower Cretaceous. The exploration goals were to seismically delineate the edges of an incised valley and to distinguish between sandstone and shale valley-fill sediments. The valley edges were defined by P-P and P-S seismic character changes. Within the incised valley, a decrease in Vp/Vs was interpreted to indicate sandstone sediments, while increasing Vp/Vs toward the northwest indicated increasing shaliness within the incised valley.