Marie Tharp: The Oceanographer Who Mapped the Ocean Floor

Marie Tharp was an American geologist, oceanographer, and cartographer whose pioneering map of the seabed highlighted the world’s hidden underwater structures. Through her discoveries and work, Tharp significantly advanced the field of oceanography, bringing groundbreaking insights into the movement of oceanic plates and the tectonic structure of the Earth’s oceans.

Marie Tharp’s Childhood

Marie Tharp was born in Ypsilanti, Michigan, on July 30, 1920. She was the daughter of William and Myrtle Tharp, who instilled in her a passion for nature and the outdoors.

Tharp often accompanied her father on birdwatching and naturalist trips. As she developed an early interest in nature and science, Tharp spent her free time studying geology and looking for fossils with an older brother.

Education and Early Career

In 1942, Tharp graduated from Ohio University summa cum laude with a bachelor’s degree in English. She initially wanted to pursue a graduate degree in geological sciences, but none of the universities she applied to accepted female geology students at the time.

In 1948, Tharp was accepted into the University of Michigan’s doctoral program in geological sciences. She became a leading geology student and after graduating in the spring of 1952, Tharp found a job in American oil exploration.

Work With Bruce Heezen

In 1953, Tharpe came across a job advertisement for a position as a research assistant at Columbia University’s Lamont Geological Observatory in Palisades, New York. At Lamont, Tharp worked alongside Bruce Heezen, a marine geologist and explorer, to develop a detailed seafloor mapping project. Together, they created an unprecedented map of the seafloor that utilized sonar data collected while exploring the ocean’s depths.

The Invention of the First Oceanic Floor Map

Beginning in1954, Tharp moved the seafloor mapping project forward by plotting the sonar data on 11-by-17 inch topographic reliefs. Tharp used a system of colored pens, shading, and arrows to represent the massive expanse of the ocean floor.

Using a grid system, Tharp filled in the dark patches with sonar data, shaping a picture of the varied topography and geographical structures of the ocean floor. In 1977, after collecting data from research vessels and sonar recordings adapted from allied submarines during World War II, Tharp finally completed the first scientific map of the ocean floor.

The Contributions of Marie Tharp

Tharp’s seafloor map brought greater understanding to the field of oceanography. Her map was one of the first to reveal the existence of mid-ocean ridges and deep-sea trenches.

The oceanic ridges Tharp discovered were the most important features of her map, indicating how the sea floor spreads in a process known as Seafloor Spreading. This critical discovery supported the theory of plate tectonics, a revolutionary concept which linked many of Earth’s geological processes.

The Significance of Marie Tharp’s Work

Marie Tharp was one of the first women to make significant inroads in the relatively untapped field of oceanography. She pioneered the use of mapping techniques and sonar data to describe the physical features of the ocean floor and brought light to the geological processes at work beneath the ocean’s surface.

Drawing from her passion of nature, Tharp brought forth groundbreaking theories to the study of oceanography. Her revolutionary mapping project made her a leader in the field of seismology and tectonic structure, a pioneering woman whose discoveries still inspire researchers today.

Enduring Legacy

Throughout her career in oceanography, Tharp earned a number of awards and accolades for her contributions to the field. In 1973, she was inducted into the Women in Science Hall of Fame, and in 2008, a US research vessel was named after her.

Marie Tharp’s legacy is represented in her map, a symbol of the pioneer she was in the field of oceanography. Thanks to Tharp’s groundbreaking contribution, scientists now understand the movements of the Earth’s tectonic plates and how they impact seismology and oceanography.