More information about the individual USGS surveys conducted as part of the northern Cape Cod Bay project can be found on the Woods Hole Coastal and Marine Science Center Field Activity webpage:
06012: <http://quashnet.er.usgs.gov/data/2006/06012/> 07001: <http://quashnet.er.usgs.gov/data/2007/07001/> 07002: <http://quashnet.er.usgs.gov/data/2007/07002/> 07003: <http://quashnet.er.usgs.gov/data/2007/07003/> 08002: <http://quashnet.er.usgs.gov/data/2008/08002/>
Field Activity 07002 SEA SWATHplus backscatter: The winch used to deploy and retrieve the Klein 3000 towfish was inoperable between Aug 1-2, 2007. During this time, the acoustic backscatter collected with the 117 kHz SEA SWATHplus interferometric sonar was used to fill the gap in the Klein 3000 backscatter. The SWATHplus transducers were mounted on a rigid pole, approximately 2.6 m below the water line, along the starboard side of the R/V Megan T. Miller. Real-time kinematic (RTK) GPS navigation data were provided by an Ashtech Z-Surveyor Extreme receiver (an Ashtech BR2G DGPS was used as a backup navigation system) and recorded to the raw data files (SXR) via the SWATHplus (version 2.07) acquisition software. A conservative estimate of positional accuracy is likely <1 m.
Field activities 07001 and 08002: The Klein 3000 towfish was deployed from a davit on the port side aft on the R/V Rafael at a fixed distance that was accounted for during acquisition. Real-time kinematic (RTK) GPS navigation data were provided by an Ashtech Z-Surveyor Extreme receiver and recorded to the raw data files (XTF) via the Klein SonarPro (version 9.6 and 10.0) acquisition software. A conservative estimate of positional accuracy is ± 10 m, but when the navigation system was providing the "fixed" RTK signal, positional accuracy is likely <1 m.
Acoustic backscatter data acquisition for field activities 07001 and 08002: The Klein 3000 towfish was deployed from a davit on the port side of the R/V Rafael approximately 1 m astern and 0.5 m below the water surface.
Swath width was 100 m either side of the vessel (200 m total) for field activities 06012, 07001 and 08002. Swath width for field activity 07002 was increased to 150 m range (300 m total) because tracklines we spaced 150 m apart.