Heezen , Bruce Charles

(1924–1977) American oceanographer

Born in Vinton, Iowa, Heezen was educated at Iowa State University, graduating in 1948, and at Columbia, New York, where he received his PhD in 1957. He worked at the Lamont Geological Observatory at Columbia from 1948.

Heezen's work has contributed significantly to knowledge of the ocean floor and the processes that operate within the oceans. In 1952 he produced convincing evidence for the existence of turbidity currents; i.e., currents caused by a mass of water full of suspended sediment. Their existence had been suggested by Reginald Daly in 1936 and proposed as the cause of submarine canyons. Heezen used precise records available from the 1929 Grand Bank earthquake to study these currents. As the area off the Grand Bank was rich with communication cables, exact records of the disturbance caused by the earthquake had been obtained. He was able to reconstruct the movement down the bank of about 25 cubic miles (100 cubic km) of sediment moving with speeds approaching 50 miles per hour (85km per hour).

In 1957, in collaboration with William Ewing and Marie Tharp, the existence of the worldwide ocean rift was demonstrated and its connection with seismic activity postulated. In 1960 Heezen argued for an expanding Earth in which new material is emerging from the rift, increasing the oceans' width and pushing the continents further apart. Such a view, based on the grounds that the gravitational constant decreases slowly with time, had been suggested earlier by Paul Dirac, but received little support in the early 1960s, particularly when a more plausible mechanism was suggested by Harry H. Hess in 1962.