DEPOSITIONAL TURBIDITY CURRENTS LADEN WITH POORLY SORTED SEDIMENT

A layer-averaged model for steady, spatially developing turbidity currents laden with poorly sorted sediment is presented together with laboratory experiments conducted to test several assumptions involved in the model development and to gather basic information about such flows and the sediment deposits that they generate. Measured flow velocity and sediment concentration profiles displayed a good degree of similarity and facilitated the evaluation of shape factors. The amount of sediment deposition and grain size of the deposits were found to decrease monotonically with distance from the source. The ability of the theoretical model to reproduce the depositional pattern and grain-size variation with distance was tested using data from a strongly depositional current. The laboratory observations were reproduced fairly well by the model.