A 2014 ASSESSMENT OF GEOMORPHIC CHANGE IN THE MONTEREY CANYON USING HIGH-RESOLUTION MULTIBEAM ECHOSOUNDER
Located off the coast of Moss Landing, CA, the Monterey Canyon is one of the largest submarine canyons in North America. Previous research indicates the Monterey Canyon is undergoing active geomorphological change characterized by a state of dynamic equilibrium.
In this research paper we (contributors described below) hypothesized that changes in sediment volume, canyon
rim, and axial channel morphology will provide further evidence of this dynamic
equilibrium.
In order to quantify changes in sediment volume and canyon morphology, we acquired multibeam echosounder data in the spring of 2014 using the R/V VenTresca to generate a digital elevation model. We then compared the spring 2014 data to previous surveys, obtained from the California State University, Sea Floor Mapping Lab. through raster subtraction and digitization.
The change in sediment volume from 2013 to 2014 was 898,000 m³ ± 483,000 m³ which was two times the rate of change from the prior two year period and three times the rate of the overall 2008 to 2014 period.
The results of this study confirmed our hypothesis that the geomorphology of the Monterey Canyon head is in dynamic equilibrium and that changes in sediment volume, canyon rim, and axial channel exhibit oscillations of increasing and decreasing areal extents over time.
Sediment volume change showing location and magnitude of net erosion or deposition at the Monterey Canyon head over designated years. Warm colors show areas of erosion and green colors denote areas of deposition, change of 1 m is excluded. A) raster subtraction of spring 2014 and spring 2008, plotted on 2008 3 m hillshade bathymetry , B) raster subtraction of spring 2014 and 2013, plotted on 2013 3 m hillshade bathymetry and C) raster subtraction of spring 2013 to summer 2011, plotted on 2011 3 m hillshade bathymetry.
Contributions
During this project I worked with Rikk Kvitek, director of the CSUMB Sea Floor Mapping Lab, and fellow CSUMB M.S. students, including Winn Mcenery,
Kyle Olejniczak, Nick Sadrpour, and John Urness.
The materials we produced added to the general scientific knowledge of the dynamics of the Monterey Canyon and the data we collected during this project are available on the CSUMB Sea Floor Mapping Lab Data Library