Some programs developed during the Upper Mantle Project, e.g., the studies of continental margins and island arcs, world rift system, and Andean geophysical program, were long-term efforts that would certainly extend beyond the termination of the UMP. This was explicitly stated by J.M. Harrison, then President of ICSU, in his 1966 announcement of the designation of 1968–1970 as the terminal phase of the UMP.
In 1968 various countries recognized the need to begin planning of a long-range effort to follow the UMP and to capitalize on the important developments that were being called a ‘revolution in earth sciences.’ A recommendation to this effect was made in April 1968 by AGU and the Geophysics Research Board (See June 1968 Transactions, pp.448 and 502). Later in 1968, with the approval of ICSU, IUGG and IUGS formed an ad hoc committee to consider plans for a long-range program of solid-earth studies. On the basis of the recommendations of the ad hoc committee (See February 1970 EOS), ICSU established the Inter-Union Commission on Geodynamics to plan and coordinate the Geodynamics Project. The Geodynamics Commission held its first meeting in Flagstaff, Arizona, in June 1970. The commission prepared the following statement of objectives of the Geodynamics Project which was approved by the ICSU General Assembly, September 1970.