Name

Marie Tharp

Career

Science

Occupation 1

Columbia University geologist

Occupation 2

Oceanographic cartographer

Region

The World

Era

Maritime Nation To 1950 (1921-1950)

Born

1920

Text

It was through Tharp's astute observations that the Atlantic Rift Valley was first discovered, which paved the way for acceptance of the theories of plate tectonics and continental drift. Tharp may be best known, however, for creating the first detailed maps of the ocean floor around the globe based on sonar, maps that have since become modern scientific icons. Tharp was able to study geology in the 1940s because of World War II, when the loss of men to the military led the University of Michigan to open its Geology Department to female students. "I never would have gotten the chance to study geology if it hadn't been for Pearl Harbor," she has said. She graduated with honors and earned an advanced math degree while working her first job (for Stanolind Oil in Tulsa, Oklahoma), yet Tharp was "hooked on research" and came east to find a position. She found one, as a mere assistant to a graduate student named Bruce Heezen, when she joined the staff of the Columbia geology department in 1948. "Can you draft?" was the defining question in her interview with the legendary Maurice "Doc" Ewing, who would soon found what is now Columbia's Lamont-Doherty Earth Observatory in Palisades, NY.

For the next several years Tharp, daughter of a surveyor who made soil classification maps for the U.S. Department of Agriculture, sat at a desk plotting profiles of segments of the ocean floor based on data from soundings taken by Ewing and Heezen. Each segment covered one degree of latitude by one degree of longitude. When Tharp started piecing together the profiles, she noticed that it was not the mountains that matched up, but a cleft running down the center with peaks on each side. "I thought it might be a rift valley," says Tharp. But Heezen dismissed the idea, associated with the improbable concept of continental drift, as "girl talk." Data soon showed earthquakes occurring along rift lines, confirming Tharp's hunch. The concept of plate tectonics moved into the realm of legitimate debate and later into the mainstream of earth science thought, although Tharp's name was not published on major papers put out by Ewing and Heezen. Did she resent being left out of the limelight? "I was always quite happy to be in the background," Tharp offers cheerfully. "I thought I was lucky to be part of such a talented group. We were just happy to be a team. It was very exciting in those days. We were explorers." In fact, when she took her job at Columbia Tharp did not even mention that she had an advanced degree in geology. Only in the last few years has Tharp begun to be recognized for her work. In 1998 she was honored during the 100th anniversary of the Library of Congress' Geography and Map division. The following year, she was recognized by the Woods Hole Oceanographic Institution.

Related Images

Photo by Steve Segala
Photo by Steve Segala

external image heezen-tharp1977.jpg
external image heezen_tharp1957.jpg
The work of two Columbia marine scientists, Bruce Heezen and Marie Tharp, in establishing the existence of a north-south ridge in the floor of the North Atlantic. Crucial evidence in support of theory of plate tectonics.
The work of two Columbia marine scientists, Bruce Heezen and Marie Tharp, in establishing the existence of a north-south ridge in the floor of the North Atlantic. Crucial evidence in support of theory of plate tectonics.