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Acoustic mapping of the regional seafloor geology in and around Hawaiian ocean dredged-material disposal sites

October 1, 2000

During January and February 1998 the U.S. Geological Survey Coastal and Marine Geology Team (USGS) conducted regional high-resolution multibeam mapping surveys of the area surrounding EPA-designated ocean disposal sites located offshore of the Hawaiian Islands of Oahu, Kauai, Maui, and Hawaii. The sites are all located within 5 nautical miles of shore on insular shelves or slopes. Regional maps were required of areas much larger than the disposal sites themselves to assess both the regional seafloor geology and the immediate vicinity of the disposal sites. The purpose of the disposal site surveys was to delimit the extent of disposal material by producing detailed bathymetric and backscatter maps of the seafloor with a ± 1 m spatial accuracy and <1% depth error. The advantage of using multibeam over conventional towed, single-beam sidescan sonar is that the multibeam data are accurately georeferenced for precise location of all imaged features. The multibeam produces a coregistered acoustic-backscatter map that is often required to locate individual disposal deposits. These data were collected by the USGS as part of its regional seafloor mapping and in support of ocean disposal site monitoring studies conducted in cooperation with the US Environmental Protection Agency (EPA) and the US Army Corps of Engineers (COE).

Citation Information

Publication Year 2000
Title Acoustic mapping of the regional seafloor geology in and around Hawaiian ocean dredged-material disposal sites
DOI 10.3133/ofr00124
Authors Michael E. Torresan, James V. Gardner
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Open-File Report
Series Number 2000-124
Index ID ofr00124
Record Source USGS Publications Warehouse
USGS Organization Pacific Coastal and Marine Science Center