Western Gulf of Maine Bathymetry and Backscatter Synthesis

TitleWestern Gulf of Maine Bathymetry and Backscatter Synthesis
Publication TypeReport
AuthorsWard, LG, Johnson, P, Nagel, E, McAvoy, ZS, Vallee-Anziani, M
VolumeBOEM/New Hampshire Cooperative Agreement (Contract M14ACOOO10) Technical Report
Number of Pages18
Date Published2016
Organization NameBureau of Ocean Energy Management (BOEM) Marine Minerals Branch,
LocationHerndon, VA
Keywordsbackscatter, bathymetry, Western Gulf of Maine

In July 2014 a Cooperative Agreement between the Bureau of Ocean Energy Management, the University of New Hampshire Center for Coastal and Ocean Mapping/Joint Hydrographic Center, and the New Hampshire Geological Survey was developed to assess the potential sand and gravel resources on the New Hampshire shelf and vicinity for the primary purpose of beach nourishment to enhance coastal resiliency. Of major importance to the effort was the development of high resolution bathymetric maps of the region to provide an understanding of the seafloor and to be used as a base for subsequent mapping products. Fortunately, over the last decade a number of high resolution multibeam echosounder bathymetric surveys were completed in the Western Gulf of Maine including the New Hampshire shelf. In addition, many of these multibeam echosounder surveys collected backscatter, which is the intensity of the returned acoustic signal from the seafloor and often reveals a great deal of information about the characteristics of the substrate.

Utilizing the high resolution multibeam echosounder bathymetry, as well as several older extant surveys, a synthesis was constructed for the Western Gulf of Maine. The original surveys used in this compilation were gridded over a large range (0.50 to 25 m). Therefore, the surveys were re-gridded at 4 m and 8 m for map development. Composites were also constructed of multibeam echosounder backscatter for the Western Gulf of Maine (gridded at 2m). However, due to the difficulties of combining varying surveys, the synthesis for the backscatter surveys was limited to a region off New Hampshire.

The composites for the Western Gulf of Maine Bathymetry and Backscatter Synthesis are presently available through the Center for Coastal and Ocean Mapping/Joint Hydrographic Center website at http://ccom.unh.edu/gis/maps/WGOM_4m/ (for bathymetry gridded at 4 m), http://ccom.unh.edu/gis/maps/WGOM_8m/ (for bathymetry gridded at 8 m), and http://ccom.unh.edu/gis/maps/WGOM_BS/ (for the backscatter gridded at 2 m).

Refereed DesignationNon-Refereed