USGS Coastal and Marine Geology Program

Coastal & Marine Geology Program

Field Activity Details for field activity 1975-025-FA

Other ID: FAY 004

Status: Completed

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

Funding Program(s):

Location: Georges Bank, United States, North America, North Atlantic,

Principal Investigator(s): John Grow

Affiliate Investigator(s):

Information Specialist(s):

Data Type(s): Electro-Magnetic: Gravity, Electro-Magnetic: Magnetics, Location-Elevation: Navigation, Seismics: Sonobouy, Seismics: Sub Bottom Profiler

Scientific Purpose/Goals: Leg 4 of the R/V FAY was set up to obtain approximately three reversed refraction lines on Georges Bank and to collect two to four long geophysical profiles over the continental slope and rise.


Start Date: 1975-10-20

Start Port/Location: Woods Hole, MA

End Date: 1975-10-26

End Port/Location: Woods Hole, MA

Equipment Used: Seismic refraction, Marine magnetometer, Gravity meter (wh), Loran-C, 3.5 kHz

Information to be Derived: Bathymetric maps;

Summary of Activity and Data Gathered: The seismic refraction velocities were obtained with both expendable and a new recoverable sonobuoy (with an internal digital recorder) in order to confirm velocity models for Georges Bank which had been developed on the basis of earlier reconnaissance refraction studies in the 1950s, and on the basis of interval velocities obtained from multichannel seismic systems. The gravity profiles into deep water were designed to supplement the gravity measurements over the shallow water portion of Georges Bank, which were collected on FAY 003, and to cover several USGS multichannel seismic lines where no or poor gravity data were available. The high velocity sedimentary rock layer was confimed and probably represents early Cretaceous or Jurassic limestones and dolomities. The 5.0-5.4 km/sec material beneath the outer edge of the shelf and upper continental slope probably also represents a carbonate bank or reef which existed at the shelf edge in the early or Middle Cretaceous period. Gravity data: 1640 km; Bathymetry Data: 500 km; Magnetics: 600 km; Refraction stations: 4 reversed profiles.

Staff: Bruce Ambuter, John Grow, William Jaworski, Lyle D. McGinnis, Charles Meeder, Sally Needell, Perry Parks, Stanley Locker

Affiliate Staff:
Felicity Oram (Watch Stander)
Doug Peeler (Watch Stander)
Scott Heald (Resident Technician
John Ostensen (First Mate)
James Biller (Third Mate)
Gary Yerman (2000 cubic inch Airgun specialist - Bolt Inc.); Paul Passmore (Consultant - Refraction Tech. Inc.)

Notes: Original Center People field contained: John Grow (Ch. Sci.), Lyle McGinnis (Geophysicist), Perry Parks (Gravity Technician), Bruce Ambuter (Electrical Engineer/Refraction), Bill Jaworski (Geophysicist/Deck Systems), Chuck Meeder (Refraction Technician), Felicity Oram (Watch Stander), Doug Peeler (Watch Stander), Sally Wood (Watch Stander), Scott Heald (Resident Technician, R/V FAY), Stan Locker (Watch Stander).

Location Map:


photo of Fay


Data Acquired

Survey EquipmentSurvey InfoData Type(s)Data Collected
Seismic refraction --- Sonobouy
1975-025-FA-SE-002 ( microfilm of )
1975-025-FA-SE-003 ( analog tape of seismic data)
Marine magnetometer --- Magnetics
Gravity meter (wh) --- Gravity
Loran-C --- Navigation
1975-025-FA-LN-002 ( Navigation data)
1975-025-FA-LN-001-01 ( Track Map (pdf file) Plotted track map with dates and times.)
3.5 kHz --- Sub Bottom Profiler
1975-025-FA-SE-001 ( Collection of paper record displays of seismic data( 3.5K) for lines )