Integrated three-dimensional modeling approach of stacked turbidite channels

Abstract

Hydrocarbon fields consisting of turbidite deposits are commonly more complex than anticipated because of fine-scale sedimentary heterogeneities, which complicate the reservoir characteristics. This is particularly evident in turbiditic channel complexes with lateral channel migration. The creation of fine-scale models is founded on high-resolution seismic data, incorporating all available data together with concepts of the internal reservoir architecture. The model is essential for understanding the impact of these phenomena on reservoir characteristic distributions. The lateral extents and a real distribution of heterogeneity are still unknown; thus, our modeling workflow is incorporated into an uncertainty chain to identify and measure all uncertainties with a possible effect on static connectivity. Internal channel complex fill is composed of multiple individual (elementary) channel stacks formed during repeated erosion-deposition cycles. These elementary structures allow sand transport through deep-sea areas and the preservation of slumps and slides on channel borders, resulting in the formation of internal heterogeneities. The sideways and downdip movement of elementary channels in turbidite complexes show two typical channel patterns: lateral migration and vertical stacking. The spatial distribution of slide heterogeneities is therefore constrained by the different channel patterns. Distinguishing between these two patterns provides an understanding of heterogeneity distributions and the resulting differences in static connectivity. These contrasts can be explained as distinct preservation rates of mass-transport slide sediments within elementary channels and can thus be included in reservoir models to define preferential zones of heterogeneity preservation along turbidite complexes.