She has led more than 50 expeditions, and has authored some 70 publications. In 1969, she participated in the Tektite project where scientists lived for weeks in an enclosed habitat on the ocean floor 50 feet below the surface. By this time, she had spent more than 1,000 research hours under water, more than any other scientist who participated in the programme.
In 1970, she led the all-female Tektite II expedition. With the aim of making the public aware of the damage being done to the aquasphere, she became an outspoken advocate of undersea research, and began to write for National Geographic and to produce books and films. In 1979, Earle walked untethered on the sea floor at a lower depth than any human before or since. She travelled 1,250 feet below the ocean's surface off the island of Oahu, and then detached herself from the vessel to explore the ocean floor.
In 1982, she started Deep Ocean Engineering and Deep Ocean Technologies which design and build undersea vehicles, which make it possible for scientists to maneuver at depths that defy existing technology. She is the recipient of many international awards and has been the subject of many articles and TV programmes.