Map Quest

Soundings: The Story of the Remarkable Woman Who Mapped the Ocean Floor BY Hali Felt. Henry Holt and Co.. Hardcover, 352 pages. $30.

The cover of Soundings: The Story of the Remarkable Woman Who Mapped the Ocean Floor


Hali Felt’s quite wonderful new book disqualifies itself as a true biography for a reason that will jar any reader who feels protective of the traditional rules of nonfiction writing. Simply put, parts of it are fictional. There are several key moments in this absorbing account of the life and career of marine cartographer Marie Tharp when Felt, a first-time book author with a flowing and vivid prose style, invents scenes to fill out otherwise sizable gaps in Tharp’s life story: “I want to give [Marie’s] story a little palpable emotion, even if it isn’t hers, to try to keep her whole, a little Pangaea,” Felt explains.

Tharp’s story, in danger of being lost to history, is well worth recounting: She specialized in the challenging work of mapping the ocean floor and was among the first to explore the nature of the Mid-Atlantic Ridge, which bisects the Atlantic on a north-south line passing through Iceland. Her research informed all modern ideas of how our landmasses and oceans came to be. But despite the empirical rigor of Tharp’s work, Soundings is best read as a work of the imagination in the tradition of the best scientific discoveries, a creative exploration of innovation, love, and the way women were left out of the narrative of twentieth-century science.

Born in 1920, Tharp grew up accompanying her father, a government surveyor, on fieldwork trips, collecting arrowheads and absorbing a tough outdoorswoman independence. Inspired by a geology class in college, she found her way into a postgraduate program in petroleum geology at the University of Michigan, which led to a job with Stanolind Oil Company in Tulsa, Oklahoma. In 1948, she moved to Manhattan to follow her husband. The marriage didn’t last more than a few years, but the job she found on arrival, as an assistant and drafter of maps at Maurice “Doc” Ewing’s geophysical laboratory at Columbia University, lasted nearly the rest of her life.

Ewing’s lab, which would soon move upstate to the Hudson Palisades and become known as the Lamont Geological Observatory, was involved in a variety of projects: fossil dating, seismology, and oceanographic expeditions that took soundings, or depth measurements, done at that time by a Fathometer, a device that worked by echolocation. There, Marie met Bruce Heezen—her work colleague and romantic partner, although the details of their relationship remain conjectural. Felt conducts her fill-in-the-blanks approach to nonfiction writing with the highest delicacy here, never succumbing to the temptation to romanticize, but adding some human texture to a partnership that was mysterious even to the couple’s closest friends. Here, for example, is how she imagines an extremely awkward first encounter: “Marie presents her right hand to Bruce so that he can shake it, but he just sort of stares at it for a second.” As they forged their working relationship, Tharp took on the role of Heezen’s assistant, even though he was still a grad student and she had her master’s degree.

Tharp had studied drafting in college, and now used that experience to help Heezen plot the lab’s collection of depth soundings onto a map of the North Atlantic Ocean. When she completed the map in 1952, she noticed something that neither she nor anyone else had ever seen before: A series of notches marked the center of the Mid-Atlantic Ridge, forming a long rift valley.

The finding marked a momentous breakthrough. The continental-drift hypothesis—the idea that the jigsaw fit of South America and Africa might suggest some ancient proximity—had been circulating for years, but had been largely dismissed. Tharp’s map of the Mid-Atlantic Ridge provided the most substantial physical evidence yet to confirm continental drift: The rift represented a space where new material had emerged from inside the earth, splitting the ridge and moving the continents on their tectonic plates. Felt does a fine job brewing up the scientific as well as the personal suspense behind the triumph of this moment—and challenging the standard account of the discovery, which delivers credit to Heezen and Ewing first and Tharp last. “You have shaken the foundations of geology,” the chairman of Princeton’s geology department told Heezen—not, one suspects, using the second-person plural.

Tharp’s career-defining discovery, coming relatively early in her life, means that the second half of Soundings is slower than the first: Tharp and Heezen spent the latter phase of their careers building out from their initial breakthrough, publishing explanatory papers, defending their ideas in new settings, contending with the gradual decline of their reputations (particularly at Columbia, where they were blackballed by the aggressive Doc Ewing)—all while continuing their unconventional life together as a couple. Felt writes that after Heezen died of a heart attack in 1977, “the final thirty years of [Tharp’s] life were spent silently cataloging the middle thirty years, filing papers and maps and letters and books and folders and photographs and all matter of things relating to that map and that man and her life with them.” But even while she worked to secure Heezen’s legacy, Tharp’s own stature in the field grew more tenuous. She was kicked off projects that she and Heezen had launched together, saw her discoveries written over in the history books (one author said she had “mindlessly drawn” the map of the rift valley), and was made redundant at Lamont. She died in 2006.

Three years later, Google Earth used her map to help expand its reach underwater, laying her drawings across the previously blank-blue stretches of the ocean. Now, the publication of this extensively researched and very warmhearted re-creation of Tharp’s life likewise fills out one previously blank region of our knowledge of scientific history. One wonders what other treasures still lie buried in the deep.

Britt Peterson is a writer in Washington, DC.