USGS Coastal and Marine Geology Program

Coastal & Marine Geology Program

Field Activity Details for field activity 1992-016-FA

Other ID: 251

Status: Completed

Organization(s): USGS, Woods Hole Coastal and Marine Science Center

Funding Program(s):

Principal Investigator(s): James M. Robb

Affiliate Investigator(s):

Information Specialist(s):

Data Type(s): Location-Elevation: Navigation, Seismics: Sub Bottom Profiler, Sonar: Sidescan

Scientific Purpose/Goals: Sidescan sonar imaging of the ocean bottom around the DWDS-106 Municipal Sludge dumpsite, for support of DSRV ALVIN dives and to characterize sea-floor microtopography.

Vehicle(s):

Start Date: 1992-07-20

Start Port/Location: Woods Hole, MA

End Date: 1992-07-29

End Port/Location: Woods Hole, MA

Equipment Used: Sidescan sonar, GPS (wh), Loran-C, 3.5 kHz

Information to be Derived:

Summary of Activity and Data Gathered: AMS-120 sidescan unit with the Qmips processing system functioned very well, with only 4 hours lost when a wire termination failed apparently due to tow strumming. Site surveys were accomplished at 4 off-dumpsite sites, and two areas within the dumpsite study area were imaged and mosaicked while at sea. The data commonly show features indicating offshore-directed bottom flows. A control site (2600 m at 70 deg 40 min W) and 2 sampling sites SW of the main study area show a smooth ocean bottom, with minor flow indications, such as elongated moats or dune structures. Within the study area, in contrast, our 8-line mosaic shows striking offshore lineations, evidently erosional furrows (parts were observed last year using Jason), as well as smooth bottom where a tongue of muddy sediments overlies the furrowed surface. The furrows lie downslope from where canyons debouch. Also mosaicked with three lines was a rough area of greater relief and high backscatter that may be part of a large olistostrome (landslide block).

Staff: Jana DaSilva, William Danforth, Jane Denny, Molly Gowen, Thomas O'Brien, James M. Robb, William Schwab, Melissa Walden

Affiliate Staff:
Tom Crook - WHOI
Denzel Gleason - WHOI

Notes: Project = DWDS-106 Sewage Sludge Investigation, DWDS-106 Sewage Sludge Investigation

Location:

Deep Water Dump Site DWDS 106, Continental Rise offshore New Jersey, New York, United States, North America, North Atlantic;

Boundaries
North: 39.40347 South: 38.62736 West: -72.3567 East: -70.62746

Platform(s):

photo of Oceanus
Oceanus

Publications

Data Acquired

Survey EquipmentSurvey InfoData Type(s)Data Collected
Sidescan sonar --- Sidescan
1992-016-FA-SO-001 ( Paper sidescan mosaics: 8 without overlays, 2 with bathymetry overlain on separate acetate sheet. Data collected with AMS120 sidescan system.)
GPS (wh) --- Navigation
1992-016-FA-LN-002 ( Trackmap of 3.5 kHz survey lines from 1992 DWDS106 survey: some hand annotations.)
1992-016-FA-LN-001-01 ( Raw navigation data files.)
Loran-C --- Navigation
3.5 kHz --- Sub Bottom Profiler
1992-016-FA-SE-002 ( microfilm of )