**The title, authors, and abstract for this completion report are provided below. For a copy of the completion report, please contact the GLFC via e-mail or via telephone at 734-662-3209**
High-resolution bathymetry surveying of the nearshore zone off Drummond Island, Lake Huron
Nigel J. Wattrus2
2 Large Lakes Observatory,
University of Minnesota – Duluth
10 University Drive
Duluth, Minnesota 55812
Over 80 km 2 of high-resolution multibeam sonar bathymetry and backscatter imagery were collected in the nearshore zone (water depth < 65 m) off Drummond Island in northern Lake Huron as part of a larger study to use a large hydrophone array to track the behavior of spawning lake trout fitted with acoustic tags. The goals of the multibeam survey were to: a) generate high-resolution bathymetric information for the study site; b) generate backscatter imagery of the study site; c) classify the substrate in key areas of the study area that is based upon its acoustic response. The data reveal an extensive field of north-south directed ridges composed of coarse gravel, cobble and boulders that are interpreted to be a relict drumlin field that formed below the Laurentide Ice Sheet during the last glaciation of the area. The orientation of the ridges reflects the flow direct of the ice sheet.