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This image represents a 2x2 meter resolution backscatter mosaic of the moderate-depth portion of the NPS's Virgin Islands Coral Reef National Monument, south of St. John, US Virgin Islands. The backscatter values are in relative 8-bit (0 - 255) values, since neither intensity surface was calibrated. Soft bottom and rhodolith habitat types were delineated and classified from this backscatter image. NOAA's NOS/NCCOS/CCMA Biogeography Branch, in collaboration with NOAA vessel Nancy Foster and territory, federal, and private sector partners, acquired multibeam bathymetry data in the US Virgin Islands from 2/18/04 to 3/5/04 and 2/1/05 to 2/12/05. Data was acquired with a pole-mounted Reson 8101 ER multibeam echosounder (240 kHz) and processed by a NOAA contractor using CARIS HIPS v5.4 software. Data is in UTM zone 20 north, datum WGS84. The backscatter component of the bathymetry data were geometrically and radiometrically corrected using Geocoder 3.2.1 software. Acoustic backscatter mosaics are an important piece of information when characterizing surficial seafloor features and delineating benthic habitats. The project was conducted to meet IHO Order 1 and 2 accuracy standards, dependant on the project area and depth. All users should individually evaluate the suitability of this data according to their own needs and standards. For a complete description of the data acquisition and processing parameters, please see the data acquisition and processing reports (DAPRs) for projects: NF-04-06-VI and NF-05-05-VI (Monaco & Rooney, 2004; Battista & Lazar, 2005).