The cooperative program is designed to provide detailed geological information and an assessment of mineral resources pertaining to that part of the continental shelf beneath the coastal waters of Massachusetts. In anticipation of the development of offshore natural resources of the Commonwealth, the major focus of the research effort is directed toward the occurrance, nature and distribution of these deposits as well as establishment of baseline data for evaluation of environmental impact of exploitation. The sub-bottom profiling surveys provide the foundation for a planned program of vibracoring and bottom sampling of geological features. Laboratory analysis of the vibracore and bottom samples will evaluate the economic importance of the deposits and, coupled with the seismic data, provide information on the geology and geologic history of the area.
Location
Rhode Island Sound, Rhode Island, Westport Harbor, Vineyard Sound, Cuttyhunk Island, Nomans Land, Martha's Vineyard, Massachusetts, United States, North America, North Atlantic;
Summary
Traverses: 33 (27 in a NW-SE orientation with a line spacing of 1 nm, 6 in a SW-NE orientation with a line spacing of approximately 3 nm); Seismic data: 358 nm (663 km) and penetration of up to 125 meters below the bottom were achieved.
Comments
All seismic track lines were pre-plotted along LORAN-C navigation lines of position. This approach facilitated control of the survey vessel on the seismic tracks despite the course setting influence of wind and currents. Cape Race, Newfoundland and Dana, Indiana LORAN-C secondary transmitters were utilized as they are the most reliable and provide the best positional accuracy within the area. Navigational fixes were taken at 15 minute intervals and ship's speed over the bottom averaged 4.5 knots. The hydrophone array and catamaran float with mounted transducer were towed about 15 meters astern of the survey vessel. This configuration, coupled with ship's speed, resulted in a sound source/receiver separation of approximately 10 meters. The transducer was triggered every 0.5 second and the sweep rate of the recorder was set at 0.25 second. Only incoming seismic signals within the 200-4000 Hz frequency range were fed to the recorder. Original Center People field contained: Chuck O'Hara - Chief Scientist, Frank Jennings - Electronic Technician, Patricia Forrestal, Wayne Ferrebee, Elizabeth Winget, Susan Purdy, and Barbara Tausey.
Project = Marine Geologic Program, Marine Geologic Program
Cruise Report (pdf file) Chief Scientist's cruise report including equipment, personnel, ship movement notes, data acquisition description, and area map with simplified track map.
Composite Cruise Log (pdf file) ASTERIAS-Buzzards Bay cruise log containing seismic and navigation entries from October 1-12, 1973(FA 73005); December 2-3,1974 (FA 74017); and June 19-30, 1975 (FA 75011).
