Alternate Leg ID: ESTW 80-8
Area of Operations: Blake Escarpment, United States, North America, North Atlantic
Dates: October 18, 1980 to November 02, 1980
Objectives: Act as escort vessel during ALVIN/LULU operations. Study the morphology and map previously identified features at the top and base of the Blake Escarpment using seismic reflection profiles acquired within 30 mi. of the dive sites. Acquire marine magnetics data in the Blake Bahama Basin.
Type of Activity: Sea floor mapping
Information to be derived: Sea floor map
Summary: Overall data quality is good, acquiring one second penetration with the sparker and greater than 2 seconds penetration with the airgun. The data indicate that the Blake Escarpment is an extremely steep slope. Because of the steep slope reflections from the surface of the escarpment are usually lost, or obscured by diffractions and side echoes. Reflectors in the Blake Bahama Basin are continuous and nearly parallel, sometimes onlapping a variable size erosional bench at the base of the Blake Escarpment. The character of reflectors on the Blake Plateau is variable suggesting alternate periods of erosion, deposition and reef growth. 1800 km airgun data; 1930 km sparker data; 1885 km magnetics data; 2080 km 3.5 kHz data; 1360 km 12 kHz data.
USGS Project Number: EA
Contact: Kathy Kent ()