Meet Marie Tharp the controversial geologist who produced the first ever map of the Ocean floor

Cross-posted from: Women Rock Science
Originally published: 21.11.14


Meet Marie Tharp the controversial geologist who produced the first ever map of the Ocean floor. Her work completely turned geology upside down and proved that the ocean floor was not just a boring flat plane of mud but actually filled with extreme mountains, volcanos, canyons and moving masses. Her most controversial discovery is that of the Mid-Ocean Ridges, chains of moving mountains that cover the entire earth. At that time anyone who believed in plate tectonics or continental drift was considered an idiot, Marie’s work proved that they were in fact real.  “I was so busy making maps I let them argue [….] there’s truth to the old cliché that a picture is worth a thousand words and that seeing is believing.“


Marie was born in Michigan 1920 and had an exciting childhood following her father all over the country surveying soils, she travelled so much she ended up going to 20 different schools. After finishing she went on to Ohio University and graduated in 1943 with a degree in English and music. Like so many women, Marie got her opportunities in STEM due to WWII. There were not enough men to manage things back home and so universities all over the country were pushing women to enter their practical science programmes and strengthen the war effort. Marie instantly signed up to take a second degree in petroleum geology. Disappointingly, whilst working for the petroleum company women were banned from the field and she was stuck in an office performing simple tasks.


Marie left the petroleum industry and got her third degree in mathematics.  She then worked at Columbia University before joining Lamont geography research project under Maurice Ewing. During this time she met Bruce Heezen, an inspiring hard working student. He became her lifetime collaborator and they worked together for 30 years right up until his death. Marie set about to do something ground-breaking and enlisted Bruce to help her. She wanted to understand and map the entire ocean floor. In a time where people thought the ocean was plain and flat this was highly topical. Marie had another huge obstacle, her boss Ewing would not allow her to enter the research vessels and ships. She and Bruce came up with a plan, he would go out to the ocean to gather the raw sonar data and Marie would process it back in her office. She had to combine this with other seismological data, perform complex calculations and draw out the information on the ocean floor. She would then draw the map of the ocean floor using pens, pencils and rulers and the artist Heinrich Berann would then paint her maps. Occasionally, Bruce managed to sneak her onto the research ships.


Marie’s work was so divisive that fights and conflicts happened at every turn.  The feuds between her and Bruce, her and Ewing and Bruce and Ewing were explosive. At one stage Bruce was shouting that her work was rubbish, took an eraser and erased 3 weeks’ worth of mapping work. When she and Bruce started showing their results she was immediately fired by Ewing and banned from using Lamont labs. Bruce stayed loyal to Marie and was shunned by all their colleagues at the labs. Her superiors also attempted to steal credit for her work and published some of her findings without her name. She had to turn her entire home into a geological office with assistants in every room and struggled financially for several years. The mapping work took decades and was completed in 1977, just as it was completed Bruce passed away of a heart attack. Their map was so accurate and so well done that it is still the desired ocean floor map used today. Space satellites have since taken pictures of the ocean floor and found Marie’s map to be accurate.

You can see videos on Marie here and here


Women Rock Science : A site dedicated to celebrating the achievements of women and girls in science

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