High-Resolution Geologic Mapping of the Sea Floor Offshore of Massachusetts

Jeffreys Ledge is a glacial deposit which stretches 33 miles from the coast of Rockport, Massachusetts to just southeast of Cape Elizabeth, Maine. As part of a multidisciplinary study to understand the effects of the Western Gulf of Maine Closure Area, the University of New Hampshire, in collaboration with NOAA has carried out two sonar surveys of southern middle Jeffreys Ledge. The first survey at the end of 2002 used a Reson 8101 (240 kHz) multibeam sonar and the second, in the fall of 2003, used a Reson 8125 (455 kHz) multibeam sonar, a Knudsen Chirp sonar (3.5 kHz) and a Klein 5500 Side Scan Sonar (455 kHz). Numerous other UNH cruises collected both box cores and videography and will continue to do so in subsequent years.

Cooperators: National Oceanic and Atmospheric Administration (NOAA), University of New Hampshire (UNH).

High-Resolution Geologic Mapping of the Sea Floor Offshore of Massachusetts, Jeffreys Ledge. Click on figure for larger image.

Project Status

Maps Available

• Western Gulf of Maine Closure Area ( WGOM Closure Area) Shows that area which was closed to fishing in 1997

Preliminary Results

This study is in the data processing stage. Only Multibeam data is available.

• Map showing overview of survey activities in Jeffreys Ledge.
  
  
• Map showing multibeam bathymetry (Reson 8101) of Jeffreys Ledge.
  
  
• Map showing multibeam bathymetry (Reson 8125) of Jeffreys Ledge.
  
  
• Map showing example of trawl mark.

Link to Center for Coastal and Ocean Mapping (C-COM)/ Joint Hydrographic Center (JHC)

For more information:

Mashkoor Malik or Larry Mayer
Center for Coastal and Ocean Mapping
University of New Hampshire
24 Colovos Roadbr
Durham, New Hampshire 03824
larry.mayer@unh.edu