Quantitative Interpretation of 4D-3C Seismic Data for an Oil-sands Reservoir

Quantitative interpretation based on time-lapse joint PP-PS inversion and rock physics models were used to estimate the probabilities of three stages in the production cycle of an oil-sands reservoir located in the Athabasca Basin of Alberta, Canada. The ultimate goal of this work was to use seismically-derived elastic properties for imaging steam chamber extension, changes in fluid saturation within the reservoir, the extension of the warmed bitumen (future production zones), and temperature distribution inside the reservoir. A rock physics model was created to define three stages of production: “in situ”, “mobilized oil” and “displaced oil”. For each of the three stages, probability density functions (PDFs) were defined using the time-lapse elastic properties logs. Seismically-derived elastic properties, resulted from our deterministic time-lapse joint PP-PS prestack inversion, were matched to the rock physics model in the reservoir, and the clusters derived from crossploting time-lapse seismic data were projected in the 3D volume.