2006 Philadelphia Annual Meeting (2225 October 2006)
Paper No. 151-12
Presentation Time: 4:15 PM-4:30 PM


WARD, Larry G.1, MALIK, Mashkoor2, CUTTER, G. Randall3, BRODEUR, Melissa4, GRIZZLE, Raymond5, MAYER, Larry A.2, and HUFF, Lloyd2, (1) Department of Earth Sciences, University of New Hampshire, Jackson Estuarine Laboratory, 85 Adams Point Road, Durham, NH 03824, lgward@cisunix.unh.edu, (2) Center for Coastal and Ocean Mapping, University of New Hampshire, Durham, NH 03824, (3) NOAA, Southwest Fisheries Science Center, La Jolla, CA 92037, (4) Jackson Estuarine Laboratory, University of New Hampshire, 85 Adams Point Road, Durham, NH 03824, (5) Department of Zoology, University of New Hampshire, Jackson Estuarine Laboratory, 85 Adams Point Road, Durham, NH 03824

Jeffreys Ledge, a glacial remnant located on the inner continental shelf off New Hampshire, forms a major morphologic feature in the Gulf of Maine. In addition, Jeffreys Ledge is extremely important to Gulf of Maine fisheries. As part of a comprehensive study of the Jeffreys Ledge ecosystem, high resolution bottom mapping using multibeam sonar, videography, and bottom sediment sampling was conducted from 2002 to 2004. The mapping effort focused on an area 18.5 by 27.8 km (10 by 15 nautical miles) that included portions of Jeffreys Ledge and the surrounding basins. In addition, half the study area was located inside the Western Gulf of Maine closure area, allowing comparisons to be made between areas where ground fishing is permitted and closed areas. The multibeam survey covered 85% of the study area at a resolution of ~5m and a smaller area (2 by 3 km) at ~2m resolution. Ground truth stations were established throughout the study area with 166 videography and 149 sediment sampling stations. Bottom maps are being developed and integrated in GIS-like environments and will include classifications based on sediment grain size, sediment and morphologic types recognized in the video, and multibeam surveys. Preliminary results show the expected relationships among morphologic features, sediment types, and bottom habitats. In addition, anthropogenic effects are discernable. This presentation will discuss the sampling approach, methodologies, results, and implications to bottom mapping and fisheries management.

2006 Philadelphia Annual Meeting (2225 October 2006)
General Information for this Meeting
Session No. 151
Marine/Coastal Science
Pennsylvania Convention Center: 109 AB
1:30 PM-5:30 PM, Tuesday, 24 October 2006

Geological Society of America Abstracts with Programs, Vol. 38, No. 7, p. 377

© Copyright 2006 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.