The tsunami that devastated ancient Britain 8,200 years ago: study shows how giant tidal waves destroyed 379 miles of the coast of Scotland
- Sheffield-led researchers analyzed debris left by the tsunami
- Based on their analysis, they modeled the impact of the wave on the Scottish coast
- They showed that the wave spread up to 30 kilometers inland
- If the wave had struck today, it would have destroyed entire cities, the team said
The “Storegga slide” – an underwater collapse 8,200 years ago that triggered a huge tidal wave – destroyed 376 miles of the Scottish coast, according to a study.
Had it happened in the present, with our higher sea levels, it would have destroyed entire cities – like Montrose in Angus, which today has 12,000 inhabitants.
The 30 meter long wave that caused Britain’s largest natural disaster in 11,000 years was triggered by a landslide in the Norwegian Sea of 36,680 square miles.
Sheffield University-led researchers analyzed and dated sedimentary deposits left by the ancient tsunami to model the wave’s impact on the Scottish coast.
This enabled them to reveal for the first time that the monstrous wave managed to travel up to 30 kilometers inland in some places.
Scroll down for video
Sheffield University-led researchers analyzed and dated the soil debris left by the ancient tsunami to model the wave’s impact on the Scottish coast. Pictured: the model of the Montrose Basin showing the extent of the inundation of the coast by the wave (in darker blue)
“Although the Storegga tsunami has been known for years, we can for the first time model how far the tsunami wave moved inland from the Scottish coast,” said author Mark Bateman of the University of Sheffield.
“While there is no similar threat from Norway today, the UK could still be at risk from flooding from potential volcanic eruptions around the world, as predicted in the Canary Islands.”
“These would cause a similar resulting tsunami wave due to the amount of material that would be displaced by the volcano.”
“These models give us a unique window into the past to see how the country was and could be affected again.”
The Storegga tsunami was triggered when submarine glacial and interglacial sediments shifted on the coastal slopes of the Norwegian continental shelf.
In their study, Professor Bateman and colleagues examine deposits in Maryton, Aberdeenshire – and date the sediments using luminescence techniques.
This enabled them to determine the age, number and relative strength of the tsunami waves that had struck the Scottish coast.
The Storegga tsunami was triggered when submarine glacial and interglacial sediments shifted on the coastal slopes of the Norwegian continental shelf. Pictured: a map with the source of the Storegga tsunami (in dark blue) with estimates of wave heights at different locations in yellow. The red circle represents the Montrose Basin study area in eastern Scotland
The 30 meter long wave that caused Britain’s largest natural disaster in 11,000 years was triggered by a landslide in the Norwegian Sea of 36,680 square miles. Pictured: a model of the tsunami as it would have been recorded in Eastern Scotland based on modern bathymetry
Pictured: a tsunami wave map showing the distribution of the first (top) and second (bottom) waves to hit the UK coast
“Thirty years ago, identification of the Storegga tsunami flood” […] was groundbreaking in recognizing that underwater landslides are a major threat, ”said Dave Tappin of the British Geological Survey, who was not involved in the present study.
The new research, he added, “provides important new insights into understanding the Storegga tsunami flood.”
“The research underscores the importance of applying new scientific techniques to previously studied events and thereby improving our knowledge of their effects.”
The full results of the study were published in the journal Boreas.
THE STOREGGA UNDERWATER LANDSLIDE – THE BASICS
The ocean floor can fail when physical conditions change, just like on land, resulting in an underwater landslide.
These mass movements of huge amounts of sediment are known as submarine landslides or “slides”.
The ocean covers over 70 percent of the planet, so there are likely to be many more landslides offshore than on land.
Submarine landslides can be found even at very low angles of inclination – up to 1 °, and mapping them underwater is difficult and expensive.
More than 8,000 years ago, a massive underwater landslide occurred off the coast of Norway.
These Storegga Slide resulted in a tsunami that hit the north east coast of the UK.
The area of the Storegga slide is about the size of Scotland.
About 791 cubic miles (3,300 cubic kilometers) of sediment slid down – much of it as large blocks up to a kilometer in diameter.
Previous studies have shown that similar events occurred in this area approximately every 100,000 years.
However, new evidence from a recent University of Dundee study suggests that smaller underwater landslides can be much more common.