Abstract

Secondary oil migration through carrier beds plays an important role in the formation of many oil fields. The purpose of this study is to compare present-day locations of major oil fields with numerical simulations of secondary oil migration that incorporate geostatistical models of carrier bed heterogeneity. Geostatistical models of permeability have seen widespread application in petroleum reservoir studies, but there are virtually no field-based studies of long-range oil migration that consider the impact of carrier bed heterogeneity. In this study, geostatistical models of permeability were developed using an exceptional data base of rock core analyses from the Viking Formation in the Alberta Basin The Viking is a heterogeneous sandstone carrier bed in which buoyancy and basin hydrodynamics probably impelled oil several hundreds of kilometers away from the mature source area. Spatial correlation patterns of permeability were obtained using directional variograms. Several kriged permeability maps were constructed using a variety of assumptions regarding data selection criteria. Secondary oil migration was simulated with a quasi three-dimensional model that tracks mathematical particles from the oil source area to the reservoirs. The permeability models produced different directions and distances of simulated oil migration pathways, but none compared favorably with the observed distribution of oil fields in the Viking. The discrepancy between the model and observed suggests that rock core permeameter data may be a poor predictor of paleo-permeability.

AAPG Search and Discovery Article #90937©1998 AAPG Annual Convention and Exhibition, Salt Lake City, Utah