Ancient underwater landslide caused huge tsunami ‘and could serve as a warning’


Rob Waugh
·Contributor
Mon, 28 February 2022,

The find suggested that an ancient landslide caused a tsunami. (Getty)

An ancient underwater landslide which caused a huge tsunami could serve as a warning for many nations in the Middle East.

A huge chasm in the seafloor was caused by a landslide 500 years ago which unleashed a tsunami in the area.

A researcher from the University of Miami Rosenstiel School of Marine and Atmospheric Science have warned that future movement of the seabed could unleash more tsunamis in the area in countries including Saudi Arabia and Egypt.

Earth scientist Sam Purkis, professor and chair of the Department of Marine Geosciences, spent four weeks aboard the OceanXplorer research vessel in the region.

As he and a fellow scientist were ascending from 3,000 feet during a submersible dive, Purkis noticed a startling break in the seabed.

It was an unexpected find, although not out of the question for the Red Sea, which was formed by the separation of the African and Arabian tectonic plates 30 million years ago.

Purkis said: “Immediately, I realised that what we were looking at was the result of some geological force, which had broken the seafloor.

He took rock samples, which revealed that it had been created by a landslide that likely occurred 500 years ago.

He was also able to find evidence from sediment collected north of the chasm, which showed that it probably spawned a tsunami.

Purkis warns that the nations along its coasts—including Egypt, Jordan, Saudi Arabia, and Israel—need to ensure that early warning systems are in place for both earthquakes and tsunami.

“Just a little shake in the wrong place and the whole wall could fail, leading to a much larger tsunami than occurred 500 years ago,” Purkis said.

“That area of Egypt, as well as Saudi Arabia, which are urbanising so rapidly, have certain hazards which haven’t been previously recognized, but they need to be, to avoid a future catastrophe.”

In 2018, geographers working in Shetland found evidence of two previously unknown tsunamis that hit the islands - hinting that Britain could face a far higher tsunami risk than previously believed.

Previously, it had been believed that the devastation unleashed by the ‘Storegga Slide’, an underwater landslide off Norway 8,000 years ago, had been a near-unique event.

Sue Dawson, from the University of Dundee, said, "We found sands aged 5,000 and 1,500 years old at multiple locations in Shetland, up to 43 feet above sea level.

"These deposits have a similar sediment character as the Storegga event and can therefore be linked to tsunami inundation."

The researchers analysed sand debris in lochs in Shetland to make their conclusion.