Hierarchical geocellular facies modelling of a turbidite reservoir analogue from the Eocene of the Ainsa basin, NE Spain

Abstract

Geocellular models of outcrop analogues can provide useful insights into modelling strategies for the subsurface reservoirs. A model of the outcropping Ainsa slope turbidite system was built to test the effects of different scales of heterogeneity on production in deep water systems. The modelling began with a structural reconstruction, based primarily upon the outcrop data, to remove the post-depositional structural relief of the reservoir analogue. The facies modelling workflow consisted of three nested stages, each corresponding to a different scale: (a) the first scale addressed the deterministic reconstruction of surfaces that bound sedimentary bodies; (b) the second scale related to the modelling of the interfingering at the gradational boundaries of the sedimentary bodies; (c) the third scale reproduced the internal heterogeneity within the sandstone-dominated sedimentary bodies. Flow simulation was used as a dynamic test of the differences in recovery efficiency for the different scales at which the geological heterogeneity was modelled.