Fluvial Sedimentation Controlled by Distal Subaqueous Sediment Dynamics

A Thesis submitted to the faculty of the Graduate School of the University of Minnesota by Jeré Anthony Mohr in partial fulfillment of the requirements for the degree of Master of Science, November 2006.In this study, I address a problem that incorporates the themes discussed above. The fundamental question I attempt to answer is: How do non-eustatic processes basinward of the shoreline affect large-scale sedimentation in the fluvial system? The basic idea is that in linked depositional systems, processes seaward of the shoreline can affect the behavior of the fluvial system. To answer this question, I constructed a simple conceptual model of fluviodeltaic dynamics and then conducted a series of physical experiments at Saint Anthony Falls Laboratory, University of Minnesota, Minneapolis. The conceptual model predicts that the sediment dynamics at the base of the delta foreset exert strong control on the dynamics of the fluvial system. The results of the experiments confirm that sediment dynamics at the delta toe play an important role in fluvial sedimentation in a coupled fluviodeltaic system. This thesis presents the theoretical (conceptual) model and the results of experiments designed to test the model