HR: 0800h
AN: OS41D-0508    [Abstracts]
TI: EXPERIMENTS ON SUBMARINE KNICKPOINTS
AU: * Toniolo, H
EM: ffhat@uaf.edu
AF: Water and Environmental Research Center -University of Alaska Fairbanks, PO Box 755900, Fairbanks, AK 99775 United States
AU: Cantelli, A
EM: cante004@umn.edu
AF: Saint Anthony Falls Laboratory - University of Minnesota, 3rd Ave. @ Mississippi River, Minneapolis, MN 55414 United States
AB: The results of a laboratory study on the upstream migration of submarine knickpoints are presented. The main goal of this research was to obtain the formation of these features at laboratory scale. In order to achieve the objective, eight experiments using different materials were conducted in a flume at the Saint Anthony Falls Laboratory, University of Minnesota. The sediment used in these experiments was: kaolin clay, silica flour and fine sand. Silica flour and fine sand were used as single sediment in four experiments. The other four experiments consisted of a combination of the previous materials. The total sediment concentration in the experiments was 5% (one experiment) and 10% (seven experiments) by volume. The discharge ranged from 0.011 to 0.055 l/s. The experiment started with an initial slope in the channel bed of 15%. The bed deposit inside the flume was built up as the experiment progressed. Knickpoints were observed in six of the eight experiments. They were formed when one material or a combination of them was used in the tests. Initial calculations on the upstream migration velocity indicate values in the vicinity of 0.5 mm/s.
DE: 9800 GENERAL OR MISCELLANEOUS
DE: 4558 Sediment transport
DE: 3022 Marine sediments--processes and transport
DE: 3045 Seafloor morphology and bottom photography
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting