The details of how sedimentary processes ultimately create the stratigraphic record are the result of complex interactions among many influences. Here, Sittoniet al. investigate sediment transport processes and alluvial sedimentary deposits formed by topography driven flow expansions, a deposition mechanism which complements with the parallel and recognized research thread of jet driven deposits. In topographic flow expansions, coupled topography and flow (not only flow, as in jets expansions) determine the characteristics of the deposits. The flow regime over topographic expansions is unchannelized at large aspect (flow width to depth) ratio. The characteristic depositional body produced by topographic flow expansions is a relatively thin, tabular sand body with flat base and slightly convex top, comparable to some "sheet flood" deposits described in the stratigraphic record. This work improves understanding and predictive capabilities of occurrence and characteristics of these deposits, and may be significant for subsurface exploration.
Geometry, flow, and sediment transport of alluvialdeposits induced by topographically driven flow expansions by Luca Sittoni, Chris Paola, and Vaughan Voller