THE ROLE OF CONVECTIVE SEDIMENTATION IN DEPOSITIONAL ENVIRONMENTS

In coarse-grained materials (usually coarser than 1 mm), sedimentation occurs due to ballistic settling. However, when sediments become sufficiently fine, delivery of sediment to the bed is strongly related by the interaction of turbulence and convective plumes of denser, more concentrated sediment-laden fluid. Our research group has documented a number of depositional environments where sedimentation by convective processes is dominant. From these observations and affiliated laboratory experiments, we have identified the environmental conditions under which these types of deposits form. These constraints should be extremely helpful in interpreting fine-grained, clastic sequences.