Three-Dimensional Seismic Lithologic Modeling to Delineate Abruptly Changing Reservoir Facies: Case History from Alberta, Canada: ABSTRACT

Abstract

Although river-channel reservoirs are attractive because of their potential high porosity and permeability, they are difficult to develop because of abrupt variations in sand and shale distribution. The Taber-Turin area of Alberta Canada, is a known oil province characterized by such reservoirs. To delineate potential reservoirs in detail, a 4-km/sup 2/ three-dimensional seismic survey was carried out, resulting in a uniform grid with traces 20 m apart. Data were wavelet processed, corrected for near-surface time anomalies, and migrated three-dimensionally. The seismic lithologic modeling (SLIM) process was then applied to provide a thin-layer interpretation of the processed data. Although the initial model for the SLIM process was based on information from only one borehole (primarily for calibration purposes), the derived velocity model showed detailed evidence of the thin glauconitic reservoirs (0-30 m thick) that are the targets of the delineation effort. All six boreholes drilled in the area (four producers and two dry) are consistent with the SLIM interpretation. Using the SLIM results, three additional boreholes have been proposed, and drilling results will be available by spring 1986.