HR: 0800h
AN: H41B-0504 [Abstracts]
TI: Morphology and forcing agents of the Monterey Canyon System: a quantitative geomorphic analysis
AU: * Taramelli, A
EM: ataram@ldeo.columbia.edu
AF: Lamont Doherty Earth Observatory of Columbia University, 9W Palisades, New York, NW
10964, United States
AU: Aiello, I W
EM: iaiello@mlml.calstate.edu
AF: Moss Landing Marine Laboratories, 8272 Moss Landing Road, Moss Landing, CA 95039,
United States
AU: Melelli, L
EM: lmelelli@unipg.it
AF: University of Perugia Earth science Department, P.zza Università , 1,
Perugia, PG 06100, Italy
AU: Seeber, L
EM: nano@ldeo.columbia.edu
AF: Lamont Doherty Earth Observatory of Columbia University, 9W Palisades, New York, NW
10964, United States
AU: Sorichetta, A
EM: sorichetta@hotmail.com
AF: School of Earth and Environmental Sciences, Queens College of CUNY, 65-30 Kissena
Blvd Flushing, New York, NY 11367, United States
AB:
Landforms are shaped by tectonics and climate, which control deformation, deposition, and erosion at the
fluid/solid interface. The recent re-emergence of geomorphology was spurred by the realization that the shape of
the land is not only the result of many processes, but it also affects them. Tectonics builds mountains and
geomorphic agents and climate conditions modify them. Thus geomorphologic processes and tectonics are
major agents of change and landform is the variable that links them, the expression of a steady-state equilibrium
controlled by multiple feed-backs. Measuring and parameterizing the shape of the landscape is the first step in
understanding many natural processes critical to environment, such as terrain instability and fluid circulation.
Furthermore, a multidimensional parameterization of the land surface (e.g., geomorphic indices) is useful in
comparing different landforms and in isolating the effect of specific factors, such as the level of tectonic activity.
So far geomorphology has dealt primarily with land areas, but an expansion to the sub-aqueous environment is
already in the making due to high-resolution bathymetry increase. This research compares submarine and land
morphology as they manifest tectonics in a rapidly transform continental margin. To this end the research has
analyzed high-resolution multibeam bathymetry to interpret modern submarine processes from a study of
geomorphic change.
This research is applied on the Monterey Bay (California) due to the complex geomorphology of both the Coast
Ranges and the seafloor. Tectonic has controlled the evolution and the present geometry of the branches and
meanders of the Monterey Canyon system, one of the largest submarine canyon systems in the world. In
particular the Monterey Canyon is an erosional, presently active feature, which has resulted from both canyon
cutting and mass wasting. The deeper parts of the canyon have been progressively offset from the headward part
by strike-slip faulting, and are now located in northern Monterey Bay.
In this context a clear understanding of the physical processes that trigger submarine slumps has been the basis
of the research. The high-resolution multibeam record of the seafloor of the MBR collected by MBARI will be
analyzed to measure the parameters describing the geometry of the submarine canyons of the Monterey Canyon
System. Our quantitative geomorphologic analysis will include slope angle, sinuosity, and width of the canyon
axis and of the thalweg. The interpretation of these geomorphologic parameters will help to define active
processes along the submarine canyons of the MBR and to unveil the relationships between continental
deformation and canyon formation in a transform continental margin. Moreover, to broaden constraints on
geophysical properties and evolution of the area, we had used landform surface high resolution DEM.
DE: 1641 Sea level change (1222, 1225, 4556)
DE: 1824 Geomorphology: general (1625)
DE: 1862 Sediment transport (4558)
DE: 3022 Marine sediments: processes and transport
DE: 4217 Coastal processes
SC: Hydrology [H]
MN: 2007 Fall Meeting