Field Activity 2005-001-FA

Identifier 2005-001-FA
Purpose Map the sea floor and shallow stratigraphy of Apalachicola Bay using sidescan sonar, bathymetry and high-resolution seismic to determine the controls on the distribution of oyster beds.
Location St. George Sound, eastern Apalachicola Bay National Estuarine Research Reserve, Apalachicola Bay, Florida, United States, Gulf of Mexico, North America, North Atlantic;
Summary This first year of a two-year program to map the floor of Apalachicola Bay focused on the eastern part of the Apalachicola Bay National Estuarine Research Reserve known as St. George Sound. Weather had a major impact on the amount of data collected during this field program. Because of the shallow depth of the bay (average depth 3 m), the sidescan sonar had to be towed close to the sea surface. When the wind exceeded approximately 15 kts the surface noise degraded the sidescan sonar imagery below an acceptable quality. The only areas not mapped were the crests of the oyster bars where water was less than 2 m deep, and a narrow band in the central part of the bay that could not be completed due to weather conditions. Sidescan sonar imagery, Submetrix bathymetry, and chirp sub-bottom profiles were collected simultaneously and were navigated using RTK DGPS. Tracklines were spaced 75-100 m apart and allowed complete sidescan sonar coverage, while the line spacing was such that, in these water depths, the interferometric bathymetry imaged 30-50% of the sea floor. Some parts of the floor of the bay were covered by muddy gas-charged sediment, and in these areas the sub-bottom penetration was minimal.
Comments Original Center People field contained: Boat operator: Barry Irwin; Technicians: Chuck Worley, Emile Bergeron; Data processors: William Danforth, Brian Andrews; Transport: Barry Irwin, Dave Nichols. Project = Geologic/habitat mapping in Apalachicola Bay, FL, Geologic/habitat mapping in Apalachicola Bay, FL
25 feet
Start Apalachicola, FL 2005-03-17
End Apalachicola, FL 2005-04-14
Days in the field 30
West -84.7018
East -84.16485596
North 29.86252999
South 29.52266183


384 Woods Hole Road
Quissett Campus
Woods Hole, MA02543-1598
(508) 548-8700
Principal investigators David C Twichell
Crew members
William W Danforth
Scientist, Staff
Brian Andrews
Scientist, Staff
David R Nichols
Scientist, Staff
Emile Bergeron
Scientist, Staff
Charles R Worley
Scientist, Staff
Barry J Irwin
Scientist, Staff
Information specialist(s)
Brian Andrews
Specialist, Information
Affiliate principal Linda Rowe, NOAA
Affiliate staff Data interpretation and ground truth operations: Linda Rowe, NOAA Coastal Services Center; Assist with operations and participate in ground truth studies: Director, Apalachicola Bay National Estuarine Reserve

Data types and categories

Data category: Imagery, Location-Elevation, Seismics, Sonar
Data type: Photo, Navigation, Sub Bottom Profiler, Sidescan, Interferometric

Equipment used

Equipment Usage description Data types Datasets
Real Time Kinematic GPS Navigation (no data reported)
Knudsen CHIRP Sub-bottom Profiler Sub Bottom Profiler 1
Digital camera Photo 1
SEA SWATHplus-M 234 kHz Interferometric (no data reported)
Klein 595 100/500kHz sidescan sonar Sidescan 1


Datasets produced in this activity

Dataset name Equipment Description Dataset contact
2005-001-FA-SE-001 Knudsen CHIRP Sub-bottom Profiler DVD ROM disk of SUBMETRIX Nancy K. Soderberg
2005-001-FA-PH-001 Digital camera Deck photos of field activity operations Charles R Worley
2005-001-FA-SO-001 Klein 595 100/500kHz sidescan sonar DVD ROM disk of KLEIN Nancy K. Soderberg


Samples collected during this field activity