Marie Tharp, a trailblazing geologist and cartographer who produced some of the earliest maps of the ocean floor, was born on July 30, 1917, one hundred years ago. With blog pieces, webinars, raffles, and other events, we have been honouring her accomplishments and legacy. Continue reading here and here.
At a period when women weren't usually welcome in the scientific community, Tharp started working at the Lamont Geological Observatory (now the Lamont-Doherty Earth Observatory at Columbia University) in 1949. She overcame these additional challenges to find the mid-ocean ridges and contribute to the evidence that the Earth is composed of plates that slide over a viscous mantle. Tharp died in 2006, but her contributions to geology and oceanography have had a lasting impact.
1. She was a born mapmaker.
William Edgar Tharp, Marie Tharp's father, worked for the USDA as a soil surveyor. Young Marie loved accompanying him on his research trips as he surveyed soils in 14 states, ranging from New York to Florida and west to Idaho. According to the Geological Society of America, she used to sit in the back of her father's vehicle as a young girl "creating mudpies and generally being a nuisance." Her interest in science was probably spurred by these excursions.
Ostego County, New York soil map produced by William Tharp and associates. Tharp and others, 1940
There may have been other benefits from the fieldwork. According to Edward Landa of the U.S. Geological Survey, "One cannot help but to hypothesise that Marie Tharp's early exposure to her father's mapping work helped to establish her own sense of spatial thinking." Furthermore, he notes that "a household where education was prioritised, and a father whose career gave an example in science in general, and mapmaking in particular, were likely important influences in Marie's upbringing. In fact, mentorship and a culture of inclusion are widely seen as essential elements of initiatives to advance diversity in the workplace.
I believe I had map-making in my blood, though I hadn't expected to follow in my father's footsteps, as Marie herself once remarked.
2. If not for World War II, she probably wouldn't have been able to pursue a career in geology.
Only teaching, secretarial, and nursing positions were available for women when Tharp first attended college. She didn't find any of these interesting, so she majored in English and music.
Tharp once stated, "I never would have had the opportunity to study geology if it hadn't been for Pearl Harbor. "Girls were required to fill the positions left vacant since the men were away at war. The University of Michigan's geology department welcomed female students a year after the conflict began. About 10 of us females replied to one of their flyers from 1943 that offered employment in the petroleum business if We earned a geology degree.
Tharp joined the Stanolind Oil and Gas Company in Tulsa, Oklahoma, after earning a master's degree in geology. Tharp was left performing office tasks, such as downloading data from well logs and drawing, since the firm wasn't sure what to do with a female geologist because she couldn't go out into the field with the males, according to Gary North from the U.S. Geological Survey. She spent her spare time studying for a bachelor's degree in mathematics since she was bored at work.
In 1948, she started working at the Lamont Geological Observatory in search of a more difficult job. Because she continued to work at Lamont until her retirement in 1983, she must have found the work exciting.
3. Her coworker disregarded the data she had collected showing that continents move as "girl talk"
Tharp spotted a V-shaped notch in the middle of the mid-ocean ridge in all six of the sounding profiles she was aligning in 1952 as they ran across the Atlantic. The cleft matched up, especially in the three northernmost profiles, Tharp said, "but the individual mountains didn't match up." She reasoned that the notch must be a rift valley, where the seafloor was separating and new material was rising above the fault to form the mid-ocean ridge.
"Bruce [Heezen] moaned and muttered, "It cannot be," when I showed him what I had discovered. Continental drift appears to be the cause, according to Tharp. At the time, accepting the continental drift idea was practically considered to be a type of scientific heresy. In the United States, almost no one believed that continental drift was feasible. At first, Bruce disregarded my analysis of the profiles as "female talk."
Heezen didn't become persuaded for another six months, and it took three more years until the research was published as an abstract without Tharp's name being included.
4. By mistake, Jacques Cousteau contributed to her success.
Jacques Cousteau, a well-known ocean explorer, didn't think the rift valley actually existed. In order to disprove Tharp and Heezen, he sailed out into the Atlantic with an underwater camera gear. In an essay titled "Mappers of the Deep," Tharp stated that when his photographs and films were shown to a huge audience at the First International Oceanographic Congress in 1959, "the vast black rocks of the rift valley, speckled with white glob ooze, rose up through the blue-green sea." "Pillows of lava newly extruded from the heart of the earth" were shown in one photograph.
These pictures helped other doubters come around to the idea that the rift valley actually did exist by giving them the first true look at it.
5. She was not permitted to embark on research cruises because the first 20 years of her career.
Being a woman on a ship was still viewed as "bad luck" when Tharp started working for Lamont. Heezen went on the research cruises and gathered the data on ocean depth, and Tharp stayed in the office and turned the data into maps. It wasn't until 1968 when she boarded a study voyage.
6. She could have been a little short-tempered.
Despite being expected to act submissively in a profession dominated by men, she occasionally lost control of her love for her job. Bill Ryan, a special research scientist at Lamont, recalls walking in on Marie Tharp yelling at Heezen after learning that his 'intuition' had cost her weeks of laborious effort. She tore this massive sheet she had been using working on for a month or so,” says Ryan.
She reportedly flung erasers and ink bottles at Tharp when they disagreed over whether the mid-ocean fissure could be a sign of the seabed expanding.
Heezen and Tharp made a solid combination despite their periodic shouting battles, and she stayed committed to him. Ryan claims that Tharp was no longer able to create anything original following Heezen's tragic death in 1977 since she had lost her intellectual companion. She sobbed and stated, "I wish that Papa and Bruce could see it," in 1997 when her maps were on exhibit in the Library of Congress next to significant historical papers.
7. Her seas map was so huge that it could only be printed on one printer in the nation.
The iconic 1977 world ocean seabed map by Tharp and Heezen was 6 feet by 3.5 feet in size. According to Ryan, there was only one printer big enough to handle the task, and it was in Minnesota. The price to print the map was $40,000, or almost $170,000 in today's dollars. The initial print's quality dissatisfied Tharp, so she insisted on having it redone at significant expense.
Ryan claimed that Heezen had asked the artist Heinrich Berann to paint the map in accordance with the printer's maximum size tolerance after first learning of it. Although Berann was best known for his landscape paintings, he had worked with Tharp and Heezen for years, painting the sketches Tharp had made for the maps.
8. Considering how much of her mapmaking was instinctual, her maps are amazingly precise.
Tharp used depth information gathered by research cruises to create her historical maps. But since the ship was limited in its ability to cover the oceans, Tharp was left to fill in the gaps and attempt to understand how everything fit together. To the extent that Heezen once stated, "what people think the bottom of the ocean looks like, that is, what most scientists and informed laymen think it looks like, is what Marie Tharp thinks it looks like," she had to rely on her intuition and geological knowledge for this.
Tharp's talents, accomplishments, and legacy started to receive the respect they deserved in the latter years of her life. She received many honors, and the Library of Congress named her one of the top four cartographers of the 20th century in 1997.