Part 1-Examples from offshore mid-Norway:Screening for deep-marine reservoirs in frontier basins

摘要

This article illustrates a successful methodology used to screen a series of deep-marine depositional systems in the gigantic (> 180,000-km~2;>69,500-mi~2) Voring and More basins,offshore mid-Norway.Seismic and well data have been integrated with architectural information from selected outcrop analogs from the Delaware basin in United States and the Ainsa basin in Spain to describe the three-dimensional depositional geometries of the deep-water sedimentary systems.he examples presented document the large variability in geometry and size by illustrating seismic facies and sequences of deep-marine fan systems in the Voring and More basins. The main architectural elements are (1] basin-floor deposits characterized by constructional processes such as sheet sands and lobe forms; (2) canyons and channels with several phases of infill; and (3) slope accommodation deposits governed by the topography with a variety of infilling stratigraphic architectures.Offshore mid-Norway, the distance to sediment provenance area varies between tens and hundreds of kilometers for the deep-marine systems, and the basin-floor deposits cover up to several thousands of square kilometers. However, insight into the litho-facies distribution and architectural features of different scales seen in outcrop and subsurface data suggest that common depositional processes may be involved regardless of scale differences across a deep-water profile. In frontier basins, sand prediction will be regional in scale, and the applied methodology is a very useful screening tool to predict what part of the deep-water basin is most likely to be sand prone and also the ultimate reservoir quality.