PIs will explore the relationship between sediment loading, sediment size, wave motions and slope on the formation and the maintenance of wave-modulated turbidity currents. In a one-of-a-kind tilting wave duct, laboratory experiments will be used to constrain the physical processes responsible for gravity-driven transport in wave-dominated environments. Contrary to limited work related to the effects of turbulence on gravity currents, PIs' early experiments appear to indicate that waves can enhance gravity-driven transport owing to the "trapping" of high concentrations of sediment there. Fieldwork in several ancient environments will be conducted that will test this and other hypotheses developed during the course of the laboratory experiments. The fieldwork will also aid in the formation of new hypotheses to be tested in the lab. The field sites (Chapel Island Formation, Newfoundland; Minturn Formation, Colorado; Westaward Ho! and Bude Formations, southwest England) were chosen to highlight various shelf environments where both sediment loading and wave activity is large. These environments are one of the best records of past climate because they are both well preserved and strongly affected by atmospheric processes. In a broad sense, PIs work will aid research on turbulent suspensions, with applications ranging from chemical engineering to geomorphology. It will also help constrain the environmental conditions found in numerous shallow marine outcrops around the world. The research program is structured such that undergraduates will have an active role in both the laboratory experiments and the fieldwork.
