This data set was acquired with a ship-based Magnetometer, Echosounder Sonar, and Gravimeter during Eltanin expedition ELT54 conducted in 1972 (Chief Scientist: Dr. Rudi G. Markl). These data files are of MGD77 format and include Singlebeam Bathymetry, Gravity Field, and Magnetic Field data and were processed after data collection.