Reconstruction of subsurface sand remobilization from seismic data

Abstract

AbstractSand remobilization often occurs in deltaic depositional environments as a result of sediment load and de-watering during sediment compaction. Three-dimensional seismic data from a shelf and fan delta environment in the Central North Sea are interpreted using a colour processing technique which gives clues for reconstructing the depositional environment and remobilizing the sand. The shape and thickness of the sand remobilization features appear to be influenced by the depositional environment of parent sand. In the shallow part of the fan delta, irregular injectite geobodies are observed. In the proximal fan delta, large round saucer-shaped injectites indicate that the pressure release largely occurred in a crater-like shape. With increasing distance from the shelf break, the thickness of the sediment load and, thus, the pressure increases. Thin and extensive sheet-like injectite structures develop along faults. Some of these appear to reactivate pre-existing flanks of giant pockmarks.