Neptune's Needle

Geologist and oceanographer.

Heezen began his professional career in 1947-1948 at the Woods Hole (Mass.) Oceanographic Institution, sailing as chief scientist on an oceanographic cruise. In 1948 he was named a Roberts Fellow in Geology at Columbia University. When Ewing founded Columbia's Lamont Geological Observatory, later the Lamont-Doherty Geological Observatory, in 1949, Heezen transferred there to conduct his doctoral research with Ewing. From 1951 to 1953 he held an assistantship in geology at Columbia, and from 1955 to 1957 a research associateship. In 1957 he was appointed a senior research scientist in the Geological Observatory. In 1960 he joined Columbia's faculty as an assistant professor of geology; in 1964 he was promoted to associate professor, serving in that rank until 1977.

Heezen's first major contribution was his discovery, as a consequence of his work on his master's degree, of submarine landslides and consequent turbidity currents. Turbidity currents, flowing masses of water made dense by suspended sediment, had been observed before, but their size and widespread occurrence on the continental margins was unknown before Ewing and Heezen's study. They explained the timing sequence of submarine cable breaks in the North Atlantic Ocean after the Grand Banks earthquake of 1929 as the result of a very large, extensive turbidity current triggered by a massive slump on the continental slope margin. The discovery of turbidity currents explained the origin of deep sea abyssal plains and peculiar "graded" sediments and required extensive modification of previous geologic doctrine.

In 1952 Heezen's colleague, Marie Tharp, noted what appeared to be the cross-section of a valley on the crest of the Mid-Atlantic Ridge on six ocean floor profiles she had constructed from echo-soundings. Heezen and Ewing then analyzed the distribution of earthquake epicenters in the world's oceans and found them concentrated in the centers of the ocean basins. From this they concluded that there was an axial valley or graben on top of the Mid-Atlantic Ridge resulting from tensional deformation. Tharp and Heezen then constructed submarine topographic maps from echo-sounding records, demonstrating the continuity of the linear valleys on the world's mid-oceanic ridges for more than 45,000 miles through the world's oceans and continuing into the African rift valleys. Discovery of the mid-oceanic rifts, which implied tensional deformation, was an essential element in establishing the global concept of shifting plates in the crust of the Earth--plate tectonics--generally considered the single most important advance in geologic science during the twentieth century.

Heezen wrote The Floors of the Oceans, I; The North Atlantic (1959) with Marie Tharp and Ewing. The Face of the Deep (1959), a book on submarine photography he coauthored with Charles D. Hollister, was nominated for the National Book Award in 1972. A series of physiographic maps of the world's ocean floors, done with Tharp beginning in 1956, comprise his most visible scientific works. Heezen coauthored Hawaii to Guam (1971) and Japan to Fiji(1973), volumes 6 and 20 of the Initial Reports of the Deep Sea Drilling Project. In addition, he was author or coauthor of more than 300 scientific papers and editor or convener of six symposium volumes.

Heezen died of a heart attack on the navy's nuclear research submarine NR-1 while it was being towed to a dive site above the Rekjanes Ridge southwest of Iceland.

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Peter Richards