Turbidity currents are cascades of sediment tumbling down Earth’s 9000 submarine canyons that carry carbon, plastics and pharmaceuticals into the deep ocean. We are finally beginning to see how often these dramatic events occur.
earth
January 24, 2023
Pete Reynolds
In November 1929, a major earthquake hit the Grand Banks off the south coast of Newfoundland, Canada, and quakes reached New York. As the ocean floor shook, large amounts of sand and mud were stirred up and flowed down the canyon, gaining momentum and causing dramatic underwater avalanches. Everest he needed enough materials to make two and caused a tsunami that killed more than 25 people.
This is the largest known example of an undersea avalanche, but it was not the only one. Beneath the waves, the world’s largest avalanches regularly occur on Earth’s coasts and oceans, carving out the deepest and longest canyons on Earth. Most of the time they go unnoticed.
For hundreds of years, fish and deep-sea creatures were the only witnesses to these events. These may have been fed by nutrient-rich sediments carried out to sea or carried by ocean currents. It was proof of what was happening. However, in the last few years things have started to change.
Now, thanks to a series of experiments and a little bit of luck, we were able to actually capture these earth sculptural events. Many of the submarine canyon labyrinths were long thought to be geologically inactive, but it turns out not to be the case. Armed with new data, researchers now have a better picture of what ocean avalanches look like, how they shape the Earth, and their crucial role in trapping the carbon dioxide that warms the world. started to put together.
The deepest and longest canyon system…
