How One Woman's Discovery Shook the Foundations of Geology

WORLD OCEAN FLOOR PANORAMA, BRUCE C. HEEZEN AND MARIE THARP, 1977. COPYRIGHT BY MARIE THARP 1977/2003. REPRODUCED BY PERMISSION OF MARIE THARP MAPS, LLC 8 EDWARD STREET, SPARKILL, NEW YORK 10976
WORLD OCEAN FLOOR PANORAMA, BRUCE C. HEEZEN AND MARIE THARP, 1977. COPYRIGHT BY MARIE THARP 1977/2003. REPRODUCED BY PERMISSION OF MARIE THARP MAPS, LLC 8 EDWARD STREET, SPARKILL, NEW YORK 10976

By Brooke Jarvis

Marie Tharp spent the fall of 1952 hunched over a drafting table, surrounded by charts, graphs, and jars of India ink. Nearby, spread across several additional tables, lay her project—the largest and most detailed map ever produced of a part of the world no one had ever seen.

For centuries, scientists had believed that the ocean floor was basically flat and featureless—it was too far beyond reach to know otherwise. But the advent of sonar had changed everything. For the first time, ships could “sound out” the precise depths of the ocean below them. For five years, Tharp’s colleagues at Columbia University had been crisscrossing the Atlantic, recording its depths. Women weren’t allowed on these research trips—the lab director considered them bad luck at sea—so Tharp wasn’t on board. Instead, she stayed in the lab, meticulously checking and plotting the ships’ raw findings, a mass of data so large it was printed on a 5,000-foot scroll. As she charted the measurements by hand on sheets of white linen, the floor of the ocean slowly took shape before her.

Tharp spent weeks creating a series of six parallel profiles of the Atlantic floor stretching from east to west. Her drawings showed—for the first time—exactly where the continental shelf began to rise out of the abyssal plain and where a large mountain range jutted from the ocean floor. That range had been a shock when it was discovered in the 1870s by an expedition testing routes for transatlantic telegraph cables, and it had remained the subject of speculation since; Tharp’s charting revealed its length and detail.

Her maps also showed something else—something no one expected. Repeating in each was “a deep notch near the crest of the ridge,” a V-shaped gap that seemed to run the entire length of the mountain range. Tharp stared at it. It had to be a mistake.

She crunched and re-crunched the numbers for weeks on end, double- and triple-checking her data. As she did, she became more convinced that the impossible was true: She was looking at evidence of a rift valley, a place where magma emerged from inside the earth, forming new crust and thrusting the land apart. If her calculations were right, the geosciences would never be the same.

A few decades before, a German geologist named Alfred Wegener had put forward the radical theory that the continents of the earth had once been connected and had drifted apart. In 1926, at a gathering of the American Association of Petroleum Geologists, the scientists in attendance rejected Wegener’s theory and mocked its maker. No force on Earth was thought powerful enough to move continents. “The dream of a great poet,” opined the director of the Geological Survey of France: “One tries to embrace it, and finds that he has in his arms a little vapor or smoke.” Later, the president of the American Philosophical Society deemed it “utter, damned rot!”

In the 1950s, as Tharp looked down at that tell-tale valley, Wegener’s theory was still considered verboten in the scientific community—even discussing it was tantamount to heresy. Almost all of Tharp’s colleagues, and practically every other scientist in the country, dismissed it; you could get fired for believing in it, she later recalled. But Tharp trusted what she’d seen. Though her job at Columbia was simply to plot and chart measurements, she had more training in geology than most plotters—more, in fact, than some of the men she reported to. Tharp had grown up among rocks. Her father worked for the Bureau of Chemistry and Soils, and as a child, she would accompany him as he collected samples. But she never expected to be a mapmaker or even a scientist. At the time, the fields didn’t welcome women, so her first majors were music and English. After Pearl Harbor, however, universities opened up their departments. At the University of Ohio, she discovered geology and found a mentor who encouraged her to take drafting. Because Tharp was a woman, he told her, fieldwork was out of the question, but drafting experience could help her get a job in an office like the one at Columbia. After graduating from Ohio, she enrolled in a program at the University of Michigan, where, with men off fighting in the war, accelerated geology degrees were offered to women. There, Tharp became particularly fascinated with geomorphology, devouring textbooks on how landscapes form. A rock formation’s structure, composition, and location could tell you all sorts of things if you knew how to look at it.

Studying the crack in the ocean floor, Tharp could see it was too large, too contiguous, to be anything but a rift valley, a place where two masses of land had separated. When she compared it to a rift valley in Africa, she grew more certain. But when she showed Bruce Heezen, her research supervisor (four years her junior), “he groaned and said, ‘It cannot be. It looks too much like continental drift,’” Tharp wrote later. “Bruce initially dismissed my interpretation of the profiles as ‘girl talk.’” With the lab’s reputation on the line, Heezen ordered her to redo the map. Tharp went back to the data and started plotting again from scratch.

Heezen and Tharp were often at odds and prone to heated arguments, but they worked well together nonetheless. He was the avid collector of information; she was the processor comfortable with exploring deep unknowns. As the years went by, they spent more and more time together both in and out of the office. Though their platonic-or-not relationship confused everyone around them, it seemed to work.

In late 1952, as Tharp was replotting the ocean floor, Heezen took on another deep-sea project searching for safe places to plant transatlantic cables. He was creating his own map, which plotted earthquake epicenters in the ocean floor. As his calculations accumulated, he noticed something strange: Most quakes occurred in a nearly continuous line that sliced down the center of the Atlantic. Meanwhile, Tharp had finished her second map—a physiographic diagram giving the ocean floor a 3-D appearance—and sure enough, it showed the rift again. When Heezen and Tharp laid their two maps on top of each other on a light table, both were stunned by how neatly the maps fit. The earthquake line threaded right through Tharp’s valley.

They moved on from the Atlantic and began analyzing data from other oceans and other expeditions, but the pattern kept repeating. They found additional mountain ranges, all seemingly connected and all split by rift valleys; within all of them, they found patterns of earthquakes. “There was but one conclusion,” Tharp wrote. “The mountain range with its central valley was more or less a continuous feature across the face of the earth.” The matter of whether their findings offered evidence of continental drift kept the pair sparring, but there was no denying they had made a monumental discovery: the mid-ocean ridge, a 40,000-mile underwater mountain range that wraps around the globe like the seams on a baseball. It’s the largest single geographical feature on the planet.

LAMONT-DOHERTY EARTH OBSERVATORY

In 1957, Heezen took some of the findings public. After he presented on the Mid-Atlantic Ridge at Princeton, one eminent geologist responded, "Young man, you have shaken the foundations of geology!” He meant it as a compliment, but not everyone was so impressed. Tharp later remembered that the reaction “ranged from amazement to skepticism to scorn.” Ocean explorer Jacques Cousteau was one of the doubters. He’d tacked Tharp’s map to a wall in his ship’s mess hall. When he began filming the Atlantic Ocean’s floor for the first time, he was determined to prove Tharp’s theory wrong. But what he ultimately saw in the footage shocked him. As his ship approached the crest of the Mid-Atlantic Ridge, he came upon a deep valley splitting it in half, right where Tharp’s map said it would be. Cousteau and his crew were so astonished that they turned around, went back, and filmed again. When Cousteau screened the video at the International Oceanographic Congress in 1959, the audience gasped and shouted for an encore. The terrain Tharp had mapped was undeniably real.

1959 was the same year that Heezen, still skeptical, presented a paper hoping to explain the rift. The Expanding Earth theory he’d signed on to posited that continents were moving as the planet that contained them grew. (He was wrong.) Other hypotheses soon joined the chorus of explanations about how the rift had occurred. It was the start of an upheaval in the geologic sciences. Soon “it became clear that existing explanations for the formation of the earth’s surface no longer held,” writes Hali Felt in Soundings: The Story of the Remarkable Woman Who Mapped the Ocean Floor.

Tharp stayed out of these debates and simply kept working. She disliked the spotlight and consented to present a paper only once, on the condition that a male colleague do all the talking. “There’s truth to the old cliché that a picture is worth a thousand words and that seeing is believing,” she wrote. “I was so busy making maps I let them argue. I figured I’d show them a picture of where the rift valley was and where it pulled apart.”

By 1961, the idea that she’d put forward nearly a decade before—that the rift in the Mid-Atlantic Ridge had been caused by land masses pulling apart—had finally reached widespread acceptance. The National Geographic Society commissioned Tharp and Heezen to make maps of the ocean floor and its features, helping laypeople visualize the vast plates that allowed the earth’s crust to move. Throughout the 1960s, a slew of discoveries helped ideas such as seafloor spreading and plate tectonics gain acceptance, bringing with them a cascade of new theories about the way the planet and life on it had evolved. Tharp compared the collective eye-opening to the Copernican revolution. “Scientists and the general public,” she wrote, “got their first relatively realistic image of a vast part of the planet that they could never see.”

Tharp herself had never seen it either. Some 15 years after she started mapping the seafloor, Tharp finally joined a research cruise, sailing over the features she’d helped discover. Women were generally still not welcome, so Heezen helped arrange her spot. The two kept working closely together, sometimes fighting fiercely, until his death in 1977. Outside the lab, they maintained separate houses but dined and drank like a married couple. Their work had linked them for life.

In 1997, Tharp, who had long worked patiently in Heezen’s shadow, received double honors from the Library of Congress, which named her one of the four greatest cartographers of the 20th century and included her work in an exhibit in the 100th-anniversary celebration of its Geography and Map Division. There, one of her maps of the ocean floor hung in the company of the original rough draft of the Declaration of Independence and pages from Lewis and Clark’s journals. When she saw it, she started to cry. But Tharp had known all along that the map she created was remarkable, even when she was the only one who believed. “Establishing the rift valley and the mid-ocean ridge that went all the way around the world for 40,000 miles—that was something important,” she wrote. “You could only do that once. You can’t find anything bigger than that, at least on this planet.”

14 Retro Gifts for Millennials

Ravi Palwe, Unsplash
Ravi Palwe, Unsplash

Millennials were born between 1981 and 1996, which means the pop culture they grew up with is officially retro. No matter what generation you belong to, consider these gifts when shopping for the Millennials in your life this holiday season.

1. Reptar Funko Pop!; $29

Amazon

This vinyl Reptar figurine from Funko is as cool as anything you’d find in the rugrats’ toy box. The monster dinosaur has been redesigned in classic Pop! style, making it a perfect desk or shelf accessory for the grown-up Nickelodeon fan. It also glows in the dark, which should appeal to anyone’s inner child.

Buy it: Amazon

2. Dragon Ball Z Slippers; $20

Hot Topic

You don’t need to change out of your pajamas to feel like a Super Saiyan. These slippers are emblazoned with the same kanji Goku wears on his gi in Dragon Ball Z: one for training under King Kai and one for training with Master Roshi. And with a soft sherpa lining, the footwear feels as good as it looks.

Buy it: Hot Topic

3. The Pokémon Cookbook; $15

Hop Topic

What do you eat after a long day of training and catching Pokémon? Any dish in The Pokémon Cookbook is a great option. This book features more than 35 recipes inspired by creatures from the Pokémon franchise, including Poké Ball sushi rolls and mashed Meowth potatoes.

Buy it: Hot Topic

4. Lisa Frank Activity Book; $5

Urban Outfitters

Millennials will never be too old for Lisa Frank, especially when the artist’s playful designs come in a relaxing activity book. Watercolor brings the rainbow characters in this collection to life. Just gather some painting supplies and put on a podcast for a relaxing, nostalgia-fueled afternoon.

Buy it: Urban Outfitters

5. Shoebox Tape Recorder with USB; $28

Amazon

The days of recording mix tapes don’t have to be over. This device looks and functions just like tape recorders from the pre-smartphone era. And with a USB port as well as a line-in jack and built-in mic, users can easily import their digital music collection onto retro cassette tapes.

Buy it: Amazon

6. Days of the Week Scrunchie Set; $12

Urban Outfitters

Millennials can be upset that a trend from their youth is old enough to be cool again, or they can embrace it. This scrunchie set is for anyone happy to see the return of the hair accessory. The soft knit ponytail holders come in a set of five—one for each day of the school (or work) week.

Buy it: Urban Outfitters

7. D&D Graphic T-shirt; $38-$48

80s Tees

The perfect gift for the Dungeon Master in your life, this graphic tee is modeled after the cover of the classic Dungeons & Dragons rule book. It’s available in sizes small through 3XL.

Buy it: 80s Tees

8. Chuck E. Cheese T-shirt; $36-$58

80s Tees

Few Millennials survived childhood without experiencing at least one birthday party at Chuck E. Cheese. This retro T-shirt sports the brand’s original name: Chuck E. Cheese’s Pizza Time Theatre. It may be the next-best gift for a Chuck E. Cheese fan behind a decommissioned animatronic.

Buy it: 80s Tees

9. The Nightmare Before Christmas Picnic Blanket Bag; $40

Shop Disney

Fans of Tim Burton’s The Nightmare Before Christmas will recognize the iconic scene on the front of this messenger bag. Unfold it and the bag becomes a blanket fit for a moonlit picnic among the pumpkins. The bottom side is waterproof and the top layer is made of soft fleece.

Buy it: Shop Disney

10. Toy Story Alien Socks; $15

Shop Disney

You don’t need to be skilled at the claw machine to take home a pair of these socks. Decorated with the aliens from Toy Story, they’re made from soft-knit fabric and are big enough to fit adult feet.

Buy it: Shop Disney

11. Goosebumps Board Game; $24

Amazon

Fans that read every book in R.L. Stine’s series growing up can now play the Goosebumps board game. In this game, based on the Goosebumps movie, players take on the role of their favorite monster from the series and race to the typewriter at the end of the trail of manuscripts.

Buy it: Amazon

12. Tamagotchi Mini; $19

Amazon

If you know someone who killed their Tamagotchi in the '90s, give them another chance to show off their digital pet-care skills. This Tamagotchi is a smaller, simplified version of the original game. It doubles as a keychain, so owners have no excuse to forget to feed their pet.

Buy it: Amazon

13. SNES Classic; $275

Amazon

The SNES Classic is much easier to find now than when it first came out, and it's still just as entertaining for retro video game fans. This mini console comes preloaded with 21 Nintendo games, including Super Mario Kart and Street Fighter II.

Buy it: Amazon

14. Planters Cheez Balls; $24

Amazon

Planters revived its Cheez Balls in 2018 after pulling them from shelves nearly a decade earlier. To Millennials unaware of that fact, this gift could be their dream come true. The throwback snack even comes in the classic canister fans remember.

Buy it: Amazon

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Late MythBusters Star Grant Imahara Honored With New STEAM Foundation

Grant Imahara attends San Diego Comic-Con
Grant Imahara attends San Diego Comic-Con
Genevieve via Flickr // CC BY 2.0

Fans of MythBusters and White Rabbit Project host Grant Imahara were saddened to hear of his passing due to a brain aneurysm in July 2020 at the age of 49. Imahara, a graduate of the University of Southern California, used the television medium to share his love of science and engineering. Now, his passion for education will continue via an educational foundation developed in his name.

The Grant Imahara STEAM Foundation was announced Thursday, October 23, 2020 by family and friends on what would have been Imahara’s 50th birthday. The Foundation will provide mentorships, grants, and scholarships that will allow students from diverse backgrounds access to STEAM education, which places an emphasis on science, technology, engineering, arts, and math. (Formerly referred to as STEM, the “A” for art was added more recently.)

Imahara had a history of aiding students. While working at Industrial Light and Magic in the early 2000s, he mentored the robotics team at Richmond High School to prepare for the international FIRST Robotics Competition. Whether he was working on television or behind-the-scenes on movies like the Star Wars prequels and The Matrix sequels, Imahara always found time to promote and encourage young engineering talent.

The Grant Imahara STEAM Foundation’s founding board members include Imahara’s mother, Carolyn Imahara, and close friends Don Bies, Anna Bies, Edward Chin, Fon H. Davis, Coya Elliott, and Ioanna Stergiades.

“There are many students, like my son Grant, who need the balance of the technical and the creative, and this is what STEAM is all about,” Carolyn Imahara said in a statement. “I’m so proud of my son’s career, but I’m equally proud of the work he did mentoring students. He would be thrilled that we plan to continue this, plus much more, through The Grant Imahara STEAM Foundation.”

Imahara friend Wade Bick is also launching an effort in concert with the USC Viterbi School of Engineering to name a study lounge after Imahara. Donations can be made here.

You can find out more about the foundation, and make a donation, on its website.