Resumen
A model was developed to calculate the evolution of a notch in a dune or cliff due to wave impact. Analytical solutions were derived to the model for schematized conditions regarding forcing and dune/cliff properties. Comparisons were made with laboratory experiments where the time evolution of the notch was measured. Values of the transport coefficients in the analytical solutions were determined by least-square fitting the solutions to the laboratory data. Some of these coefficients could be related to the ratio between parameters describing the forcing and the dune/cliff strength. The evolution of the dune notch displayed a linear behavior at short times, whereas the cliff notch showed a more complex response for cases where a feedback between the notch and a beach formed seaward of the cliff occurred.Referencias
Erikson, L. and Hanson, H. 2005. A method to extract wave tank data using video imagery and its comparison to conventional data collection techniques, Computers & Geosciences, 31, 371-384. http://dx.doi.org/10.1016/j.cageo.2004.10.006
Erikson, L., Larson, M., and Hanson, H. 2005. Prediction of swash motion and run-up including the effects of swash interaction, Coastal Engineering, 52, 285-302. http://dx.doi.org/10.1016/j.coastaleng.2004.12.001
Erikson, L., Larson, M, and Hanson, H. 2007. Laboratory investigation of beach scarp and dune recession due to notching and subsequent failure, Coastal Engineering, 51, 675-696.
Fisher, J. and Overton, M. 1984. Numerical model for dune erosion due to wave uprush, Proceedings of the 20 th Coastal Engineering Conference, ASCE, 1553-1558.
Kogure, T., Aoki, H., Maekado, A., Hirose, T., and Matsukura, Y. 2006. Effect of the development of notches and tension cracks on instability of limestone coastal cliffs in the Ryukyus, Japan, Geomorphology, 80, 236-244. http://dx.doi.org/10.1016/j.geomorph.2006.02.012
Larson, M., Erikson, L., and Hanson, H. 2004. An analytical model to predict dune erosion due to wave impact, Coastal Engineering, 51, 675-696.http://dx.doi.org/10.1016/j.coastaleng.2004.07.003
Nishi, R. and Kraus, N. 1996. Mechanism and calculation of sand dune erosion by storms, Proceedings of the 25 th Coastal Engineering Conference, ASCE, 3034-3047.
Sunamura, T. 1973. Coastal cliff erosion due to waves. Field investigation and laboratory experiments, Journal of the Faculty of Engineering, The University of Tokyo, XXXII(1), 1-86.
Sunamura, T. 1976. Feedback relationship in wave erosion of laboratory rocky coast, Journal of Geology, 84, 427-437.http://dx.doi.org/10.1086/628209
Sunamura, T. 1992a. Geomorphology of rocky coast, John Wiley & Sons, England.
Sunamura, T. 1992b. A wave tank experiment on the erosional mechanism at a cliff base, Earth, Surface, Processes, and Landforms, 7, 333-343. http://dx.doi.org/10.1002/esp.3290070405
Trenhaile, A.S., Pepper, D.A., Trenhaile, R.W., and Dalimonte, M. 1998. Stacks and notches at Hopewell Rocks, New Brunswick, Canada, Earth, Surface, Processes, and Landforms, 23, 975-998.http://dx.doi.org/10.1002/(SICI)1096-9837(1998110)23:11<975::AID-ESP916>3.0.CO;2-K