Modelos 3D de análogos de reservorios sedimentarios: Aplicación al sistema de abanico costero eoceno de Sant Llorenç del Munt (Cuenca del Ebro)

Abstract

3D reservoir characterizations of analogues based on outcrop studies provide geological information that can be used for reducing uncertainty in subsurface reservoir modelling to predict interwell areas. 3D reservoir-scale models of a 133 m thick transgressive-regressive sequence (Vilomara composite sequence), in the Sant Llorenç del Munt fan-delta complex (Eocene, Ebro foreland basin), reproduce heterogeneity scales which potentially influence flow simulation predictions. Three scales were recognized and modelled: (a) transgressive and regressive tracts in which the sedimentary record is structured; (b) stacking and interfingering of facies belts and (c) sedimentary bodies which provide sedimentological variability along facies belts. In order to solve the different stacking trend of transgressive and regressive tracts by using different modelling strategies, models were compartmentalized into several sections by means of modelling bounding surfaces (maximum regression and flooding surfaces). The depositional trend of facies belts for each tract was reproduced considering the stacking angle and interfingering measures obtained from outcrop studies, while the last modelling step in this work describes the geometry, arrangement and spatial relations of sedimentary bodies observed in field. All these models are stochastic simulations built applying different statistics algorithms provided by Roxar Reservoir Modelling System.