Integrating Seismic Data in Reservoir Modeling: The Collocated Cokriging Alternative

Abstract The two sources of information commonly available for modeling the top of a structure, depth data from wells and geophysical measurements from seismic surveys, are often difficult to integrate. While the well data provide the most accurate measurements of depths there are rarely enough wells to permit an accurate appraisal from well data alone. On the other hand, the seismic data are generally less precise but more abundant. Two geostatistical methods, "external drift" and "collocated cokriging", are proposed to integrate the two sources of information. A case study is used to document the strengths and weaknesses of both approaches for constructing contour maps of the top structure and assessing the uncertainty on such maps through stochastic simulations.