Gravity anomalies over the Aleutian Trench



In 1964 the USC&GS Surveyor crossed the Aleutian trench 48 times between 165° and 180°W longitude. The data provide a basis for a free-air gravity map, a Bouguer gravity map (density 2.87 gm/cm3), and three possible crustal models that fit the results and available seismic data. The area covered lies west of an earlier gravity survey described by Peter, et al. [1965] of the Aleutian trench between 155°W and 165° longitude and 53° and 55°N latitude. As on the earlier gravity survey, which was also carried out by the U.S. Coast and Geodetic Survey, the observations were made along north-south lines spaced 20 km apart and extending about 200 km south of the island arc.