HOW DO SUBMARINE CHANNELS FORM? AN EXPERIMENTAL PERSPECTIVE

The processes involved in the initiation of submarine channels on the upper continental slope are incompletely understood. We use observations from physical experiments to explore the boundary conditions that are important for the initiation of sub-aqueous slope channels by turbidity currents. We discuss the results of three physical experiments. The first two experiments investigate the parameter space required to form channels from plunging hyperpycnal plumes at the fronts of deltas at the continental shelf-edge; the third experiment deals with channel initiation beneath sheet flow over irregular topography. Our results suggest that topographic roughness in both cross-stream and down-stream directions, and more importantly, the ratio of topographic scale to current thickness play a key role in the initiation of incisional and depositional channels by turbidity currents on the continental slope. Likelihood of channel formation increases for systems where this ratio is equal to or less than one. Likelihood of channel formation increases for systems where this.