CCOM/JHC Surveys

During the CCOM/JHC Field Hydrography Course in the summer of 2002 multibeam data was collected in Little Bay. A Reson 9001 multibeam sonar was mounted on a bow ram on the CCOM/JHC survey vessel Coastal Surveyor. The sonar operates at 455 kHz with 60 1.5 degree beams over 90 degrees swath width. Vessel attitude, heading and position were determined using an Applanix POS/MV v3.

The raw data were logged on a PC running Triton Isis in XTF format and post-processed using Caris HIPS. Tides were measured at a gauge at Jackson Laboratory at Adams Point, near the southern end of Little Bay, and phase and amplitude corrections were made for areas away from the gauge. All data were corrected to represent MLLW. Sound velocity casts were made approximately every two hours and applied to data close in time and space to the cast. Dynamic draft was determined using a level on shore and a rod on the vessel run at different speeds.

The processed data were gridded at 1m resolution using the weighted gridding algorithm built into Caris HIPS. These grids are available for download on the Available Maps and Data page.