From Mike the Mad Biologist’s blog, I learned about Marie Tharp, the woman who mapped the ocean floor. The amazing story is described in the articles below:
Seeing Is Believing: How Marie Tharp Changed Geology Forever (smithsonian.com)
Four facts about Marie Tharp, the woman whose art mapped the bottom of the sea (massivesci.com)

Credit: Lamont-Doherty Earth Observatory and the estate of Marie Tharp, from the smithsonian.com article linked below.