We know lots about these things - as the article explains. A lab I'm roughly associated with models them, here's an example: https://www.youtube.com/watch?v=UR5

We know lots about these things - as the article explains. A lab I'm roughly associated with models them, here's an example: https://www.youtube.com/watch?v=UR5NoaqpCok https://www.youtube.com/watch?v=UR5NoaqpCok The physics (IIRC) are very similar to snow avalanches. I saw a talk once that presented evidence of one in the Indian Ocean flowed half way to the Antarctic (order 1000s of km). They have been observed to scour the canyons (such as Monterey Canyon) and are hypothesized to be set up similarly to avalanches, where the sediment depositions become unstable and slide. A final bit of trivia: the photo of the mooring base shows a common oceanographic mooring construction material - used railroad car wheels. Big, super heavy and relatively cheap. I've never heard of them being recovered. Usually the important parts are detached and the wheels are left behind.