My research; Josh Allin

Hi MOOCers and ocean lovers. This here’s a little short post about my area of research, which focusses on submarine landslides. I am currently working on two different research locations; the first of which is Nazaré Canyon, offshore Portugal. Nazaré Canyon is a large submarine channel, comparable in width to the Grand Canyon. At it’s mouth (purple in the image below) the canyon is almost 5 miles across and is at a depth of over 5000 m.

 

While most people are aware of terrestrial landslides, few people  know that landslides also occur underwater. Because these canyons have steep sides, they are prone to failure from time to time, after which the sediment flows down the canyon, sometimes for hundreds of miles. This landslide more closely resembles a sandy soup. Here is a video in which you can see this process occurring.

 

 

These landslides can vary hugely in size, from small like the one in the video, to landslides that could theoretically cover the whole of the UK (Don’t worry, we’re safe from being buried). These landslides do pose one particular risk though: They can cause tsunami waves!! Here’s a video showing how that can happen. This video is observing from an underwater perspective and the waves generated above it are actually on the surface of the ocean

 

 

Landslides are a very significant oceanic process, and one which we don’t fully understand. my research focusses on records that these landslides leave behind, and what they can tell us about them. The number of landslides has changed over time, and there are many possible causes, which all helps us analyse the risk of tsunamis. This research will also help us understand how climate affects landslides, and how future climate change might change their frequency