Summary for Field Activity Number 1978-026-FA

Alternate Leg ID: CI 7-78-2

Area of Operations: North Atlantic outer continental shelf and slope, Georges Bank, United States, North America, North Atlantic

Dates: September 08, 1978 to September 27, 1978

Objectives: Determine location and frequency of mass sediment movement and other geological hazards on the North Atlantic Continental Slope (Georges Bank area) using high-resolution geophysical methods.

Type of Activity: Seismic profiling

Information to be derived: Sea floor map
Morphology

Summary: Overall data quality is excellent, with good resolution and penetration. Some areas of rough topography obscured the underlying structure. Records show slumping and other mass sediment movement occurred at several places on the continental slope adjacent to Georges Bank. Slumping occurs in scales that range from small to large and in styles that range from simple downslope creep to major dislocation. Most slump bodies are found near the base of slope with marked erosional truncations above. Records from the edge of the continental shelf show numerous buried channels of varying size and configuration. Inside the 60 m isobath extensive fields of large sand waves are present. 3.5 kHz: 218 km; Minisparker: 2669 km; Airgun: 2142 km.

USGS Project Number: EA

Contact: John Aaron ()