earth and environmental sciences
(recorded in 2006)
Listen or download interview (38 minutes, 36MB)
As a kid growing up in Minnesota, Marcia McNutt didn’t imagine her love of math and science would lead her to become a Navy Seals-trained explosives expert, an earthquake predictor and one of the world’s leading geophysicists.
Encouraged by a family in which women’s education was a tradition and a norm, McNutt excelled in school and graduated as valedictorian of her class at the all-female Northrop Collegiate School in 1970. She studied physics at Colorado College in Colorado Springs, Colorado, and then, in 1978, earned a Ph.D. in Earth sciences and geophysics from the Scripps Institution of Oceanography at La Jolla, California.
McNutt is best known for her research on exceptions to plate tectonics, the currently accepted model of how Earth’s surface works. Her studies of volcanic eruptions and earthquakes occurring far from tectonic plate boundaries, where such activity is predicted to take place, deepened geologists’ understanding of Earth’s crust and won her honors and awards from the American Philosophical Society, the American Academy of Arts and Sciences and the American Geophysical Union, of which she was president from 2000 to 2002.
McNutt was elected to the National Academy of Sciences in 2005. She is currently the Director of the United States Geological Survey, the first woman appointed to that position.
Although her family has no history of scientific bents, McNutt traces her achievements to their support and love of learning. Both her father, a small business owner, and her mother, a college-educated homemaker, encouraged McNutt and her sisters in their academic pursuits. Her family’s support and her single-sex education of which she considers herself a “strong believer” keep McNutt unencumbered by the stereotypical view that science belongs to men, she notes. She decides in high school she will study physics in college, and chooses Colorado College over Stanford “to the horror of everyone else,” she says.
McNutt studies physics at Colorado College, a small and unorthodox school where students take one class at a time in month-long “blocks.” It is there that a professor named John Lewis and his two-block course in geology change her life.
Lewis leads his geology class off campus and into the southern Rockies for two months, during which they live in the field and discover the geologic history of the region through observation, scientific reasoning and Lewis’ version of the Socratic method. The experience convinces McNutt she must do science “outside” rather than in the lab, but she continues as a physics major because the qualitative nature of geology doesn’t satisfy her. Then an independent study on an up-and-coming theory called plate tectonics shows her a mathematical and rigorous approach to geology is on its way. At her professors’ urgings, she abandons her plan to take a year off after college and heads straight for graduate school in the Earth sciences at the Scripps Institution of Oceanography, a locus for plate tectonics research.
As a National Science Foundation Graduate Fellow at Scripps, McNutt pursues her interest in plate tectonics and its predictions for how the Earth will behave under stress. The theory describes Earth’s surface as a work in progress, composed of “plates” of crust adrift and separating or colliding at their boundaries - a model that matches data on the earth’s surface remarkably well, she explains. McNutt focuses her research not on the horizontal forces at play along the boundaries, but on vertical forces that deform the plates themselves. She discusses how the solid-seeming earth can react like a trampoline or even a tub full of water if it’s under enough stress.
Although McNutt does not consider herself a member of the first generation of female oceanographers who faced severe discrimination when going out to sea, she says she encountered her share of “remaining Neanderthals.” These men knowingly or unknowingly tried to keep women out of high-profile positions under the guise of helping them, she says, advising them to take time off to be with their families or to go out to sea in groups for “protection.”
But a Navy Seal demolitions course earned McNutt special status even among the men. A bemused McNutt reflects that the weeks she spent training with the Navy Seals in undersea explosives which played a crucial role in ocean floor mapping at the time make her a necessity aboard research expeditions and “certify” she’s tough enough to go to sea.
A homesick McNutt returns to Minnesota for a year after graduate school, but soon realizes her career will stagnate there. She accepts an offer from the U.S. Geological Survey in Menlo Park, California, to work on the problem of earthquake prediction, applying her thesis research on the earth’s surface strength to their prediction program. At the time, the government agency was questioning the program’s effectiveness and the possibility of predicting earthquakes at all. Scientists had succeeded at predicting some earthquakes but failed with others, like China’s cataclysmic Tangshan earthquake in 1976.
McNutt wonders if seismic processes might be chaotic - so sensitive to all the complex details of their initial conditions as to be impossible to predict. She grows disillusioned with her work at the USGS and accepts a professorship at MIT.
McNutt’s tenure in MIT allows her to freely follow her research interests, and they lead her to the work for which she was elected to the NAS. She studies the “exceptions” to plate tectonics: places like the Hawaiian Islands and the Colorado Rockies that the theory has a hard time explaining. Her field work takes her to the volcanoes of French Polynesia, which erupt and rise “smack-dab” in the middle of plates, far from the active edges, says McNutt. She challenges the accepted view that plumes of hot material rise from the boundary between the earth’s core and its mantle to create these unusual sites.
After 15 years at MIT, McNutt returns once more to California, this time to head the Monterey Bay Aquarium Research Institute in Moss Landing. Hewlett-Packard’s David Packard founded the institute in 1987 to improve the technology available to ocean scientists through collaborations between scientists and engineers. McNutt relates the story of how Packard became interested in ocean science: it involves a covert operation, a Soviet submarine and billionaire eccentric Howard Hughes and describes how the institute’s collaborations work.
McNutt reflects on balancing her work and her life, which includes three daughters and six horses. She admits the juggling act hasn’t been easy, but says it has made her a better scientist and a happier person. When asked what achievements give her the most pride, she answers unequivocally: her daughters.
McNutt advises young people contemplating a career in science to find a promising research field while it’s still in its infancy, and to make sure they do what they love.
Last Updated: 11-24-2009
The audio files linked above are part of the National Academy of Sciences InterViews series. Opinions and statements included in these audio files are those of the interviewee and do not necessarily reflect the views of the National Academy of Sciences.