SSP3.13/GM9.10/HS11.41Sedimentological aspects of supercritical flows: Upper flow-regime structures, bedforms and fluid mechanics (co-organized)
|Convener: Svetlana Kostic | Co-Conveners: Arnoud Slootman , Miwa Yokokawa , Matthieu Cartigny
Supercritical flows affect a wide range of natural settings, e.g. glacial-outwash, fluvial, beach, deltaic, deep-sea, volcanoclastic and carbonate slope environments. Supercritical flows include catastrophic free-surface flows, subaqueous density currents, pyroclastic density currents, and katabatic winds. These flows create upper flow-regime bedforms, such as chutes-and-pools, antidunes, cyclic steps and transitional bedforms betweem antidunes and cyclic steps. Associated sedimentary structures are often ascribed a low preservation potential in the stratigraphic record as a result of their high-energy formative conditions. However, the scarcity of observations may in part be due to a lack of diagnostic criteria for their recognition. Flume experiments have been pivotal to our understanding of the morphodynamics of upper flow-regime bedforms, showing a close association with stationary waves and hydraulic jumps. Our knowledge is enlarged with studies reporting on direct measurements of supercritical flows, in particular in (glacio-)fluvial settings and, more recently, modern turbidity currents. Numerical modeling also have significantly contributed to this exciting field of research.
This session aims to bring together experimentalists, numerical modelers and field geologists with an expertise in sedimentology, fluid mechanics and related disciplines to further explore the genesis of supercritical-flow bedforms and related sedimentary structures. Students and young researchers are encouraged to submit.