Over 200 million years ago, all earth’s continents were part of a single supercontinent called ‘Pangea’. A fact, proven by Maria Tharp a geologist, and Oceanographic cartographer. Her discoveries and accurate seafloor mapping had paved the groundwork for us in understanding earth's geological past and in navigating through our ever-changing environment.
For centuries, the mysterious seafloor was thought to be flat and featureless. The first mapping technique involved lowering lead lining made of long wire and cannonball into the sea. The length was measured when the weight hits the bottom. Despite measurements made by many expeditions during the late 19th century, the vast sea remained a mystery. It became possible with SONAR technology developed by the British during WWI. The U.S Navy when on in advancing the technology, believing a map of the underwater terrain would give their submarines an upper hand on future battles.
So with the SONAR data collected on Navy Vessels, Marie Tharp was set off to work. By meticulously converting graphs and numbers, she was able to accurately map out her findings onto large canvases. In 1953, Tharp discovered the Atlantic ridge, an important piece of evidence that proved Alfred Wegener's concept of continental drift - that all earth’s continents were once a single supercontinent called 'Pangaea'. However, many dismissed her finding as impossible. Her theory was ultimately supported by Jacques Cousteau’s exploration of the very location.
In 1956, Tharp went on to discover the 'Mid-Ocean Ranges', known as ‘the backbone of earth’. The long chain of mountains was made of oceanic crust from volcanic eruptions. These eruptions were caused by two oceanic plates moving apart and interacting. Proving 'tectonic plates theory' whereby continents are still moving since they are resting on top of tectonic plates.
From aiding in warfare to laying the foundation for ocean exploration, Tharp's work helps us make sense of the world we live in. Today, where climate change takes center stage, seafloor mapping data becomes a vital tool. It forecasts coastal flooding, earthquakes, and tsunamis. As well as monitoring the ocean currents passageways that regulate the global climate.
Word by Buranee Soh Cover photo: National Geographic