The Woman Who Mapped The Ocean Floor

by Lindsay Shapka in , ,


Marie Tharp at work (source)

While exploring the Internet earlier this week, I came upon this fascinating story featured on Mental Floss. Written by Brooke Jarvis, How One Woman’s Discovery Shook the Foundations of Geology, tells the story of how Marie Tharp produced an incredibly detailed map of part of the world that had never before been seen.

She was working in the 1950s at Columbia University charting the ocean floor. The creation of sonar had suddenly enabled ships to “sound out” the precise depths of the ocean and from the readings; maps could be drawn up for the first time ever. Because it was considered bad luck to have a woman at sea, Tharp wasn’t allowed on the research trips, instead staying back at the university and translating the data as it came in.

“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.”

 Her discovery was thought to be a mistake and she was told to redo the map, but after starting over and going through the whole process again, the results were the same. She had discovered a rift in the earth’s crust and would change the way that scientist’s looked at the earth forever!

 Read the full article here.