Huge two-day underwater avalanche sent mud 1,000km into ocean
A vast underwater avalanche sent mud and sand more than 1,000km out into the ocean over the course of two days, rupturing submarine cables and disrupting internet traffic on Africa’s western coast, scientists have revealed.
The avalanche, the longest sediment flow ever recorded, travelled more than 1,100km from its source at the mouth of the Congo river along a deep ocean canyon, according to a new study.
It took place in January 2020 but the data on it has only just emerged. The slide may have gone unnoticed on land had the telecommunications cables not been broken, slowing data traffic between Nigeria and South Africa.
The event was also captured on devices that researchers had placed in the south Atlantic to measure the speed of currents and sediments. The sensors showed a flow of mud and sand accelerating from five metres per second to eight metres per second as it flooded out to sea.
“We had a series of oceanographic moorings that were hit by the event, which broke them from their seafloor anchors so that they popped up to send us an email,” Professor Peter Talling from Durham University told the BBC.
