Reflection on the discovery of mid-ocean ridges and the validation of continental drift theory
If you enjoy reading about the history of science, this is a great story: the history of geologist Marie Thorp, whose methodical plotting and cataloging of mid-ocean SONAR data led to the discovery and mapping of the mountainous ridges that bisect the world's oceans. That discovery in turn helped validate the geologic theory of continental drift, which until then had been dismissed by even serious, erudite scientists as a bit of poetry and imagination.
In late 1952, as Tharp was replotting the ocean floor, Heezen took on another deep-sea project searching for safe places to plant transatlantic cables. He was creating his own map, which plotted earthquake epicenters in the ocean floor. As his calculations accumulated, he noticed something strange: Most quakes occurred in a nearly continuous line that sliced down the center of the Atlantic. Meanwhile, Tharp had finished her second map—a physiographic diagram giving the ocean floor a 3-D appearance—and sure enough, it showed the rift again. When Heezen and Tharp laid their two maps on top of each other on a light table, both were stunned by how neatly the maps fit.An interesting read that's surprisingly heart-warming: amazing to see how facts become knowledge and knowledge leads to understanding.