The Geochemical Ocean Sections Study (GEOSECS) was a global survey of the three-dimensional distributions of chemical, isotopic, and radiochemicaltracers in the ocean.[1] A key objective was to investigate the deep thermohaline circulation of the ocean, using chemical tracers, including radiotracers, to establish the pathways taken by this.[2]
Expeditions undertaken during GEOSECS took place in the Atlantic Ocean from July 1972 to May 1973, in the Pacific Ocean from August 1973 to June 1974, and in the Indian Ocean from December 1977 to March 1978.[3]