European tsunami threatening?

The last time the tsunami swept Europe was over 8,000 years ago. But new studies show that since then the Northern European seabed has exploded many earthquakes. Just a landslide by the slopes under the continental shelf, a tsunami will engulf many Atlantic coastal cities.

The earthquake that rocked the Storegga coast between Bergen and Trondheim of Norway around 8,150 years ago was a disaster of the end of the world. The tremors tore apart many of the land in the size of the island nation of Iceland, churning out of shallow water and throwing it into the deep sea. Strong tsunamis have swept across northern Europe, crashing into Scotland waves of over 6 meters.

Can old stories repeat?

Revisit history

Many European cities from Norway to England will be removed from the map if the tsunami happens again

British Geological Survey geologist Roger Musson, based in Edinburgh, has found documents that show a different picture. Many 16th-century data refer to the big earthquake on September 19, 1508 that shook the whole of England. The epicenter is right in Scotland.

Clearly this is not a local earthquake that often occurs in Scotland and England. At least that was the theory that Musson proposed at the European Geosciences Union (EGU) conference held at Vienne (Austria) in mid-October 2006.

Years of studying in libraries, church mantras and ancient documents have pushed Musson to find many ominous evidence. The old documents show that in the years 1089, 1617, 1686 and 1847, the sea floor near the UK suffered many serious earthquakes. According to Musson, earthquakes are not only more frequent, they are getting stronger. However, it is difficult to prove Musson's hypothesis because the earthquakes along the European coast only began to be recognized by scientific equipment since the 1970s.

Roger Musson's historical discoveries have made geologists focus on the slopes on the northern continental shelf. The underwater cliffs between shallow waters and deep waters off Norway are 3,800 meters deep. An earthquake can cause sediments to lie on the slopes to slip away - like 8,150 years ago - or not?

The continental shelf is unsafe

The computer simulation of the slip land at Storegga coast, Norway caused tsunamis to spread to England 8,150 years ago

Norwegian scientists are sure that there is no risk of landslides off the coast of Storegga in the country. Geologist Tore Kvalstad asserted: All volcanic lava layers have drifted away in the massive earthquake 8.150 years ago. Tore Kvalstad has for many years studied Storegga seabed tectonics. However, the northern coast and south of Storegga are not so thoroughly studied.

A survey team of Petter Bryn experts (Oslo energy company Morsk Hydro) and Anders Solheim (International Center for Geological Danger) have just completed a geological study on Norway's west coast. The result: slippery land has occurred in many places along this coast over the past 1 million years. In 1999, researchers discovered traces of a fierce landslide in northern Norway and were only surveyed for the first time. As intense as the slide in Storegga, this landslide - named Yermak Slide - happened about 30,000 years ago and caused devastating tsunamis.

Vulnerability of knowledge

Whether this will recur depends on the mixture of sediment on the steep continental shelf of Northern Europe. So far, there has been no research on this sediment. It is a knowledge flaw that can cause serious consequences. These deposits can hide many layers of extended clay, increasing the slipperyness of continental shelf slopes. Steep sand will also be another alarming cause, because just a small shift on the ground can cause them to move away from the fragile stable position.

On the map, the dashed area shows the large area of ​​the Yermak Slide (about 45km wide) from 30,000 years ago, causing tsunamis to spread across northern European waters.

The Yermak Slide landslide threw giant plots down to 1,400 meters deep in the sea.The height of the Eiffel Tower is 350 meters which is used as a comparison rate.

Perhaps the biggest uncertainty factor is the freezing gas (methanhydrates) that serves as a weak tape that keeps sand from clinging to the slopes. In the scientific journal Eos, Angus Best of Southampton University (UK) warned that if the water level or temperature changes, this "cement" layer will disintegrate. An earthquake can also make this architecture uncertain slip away.

Norwegian scientists have designed a simulation model on computers to visualize the consequences of a super-strong slide. Just a few minutes after the landslides, 14-meter-high waves will descend on the Norwegian coast with a tragic outcome because many cities are at sea level or in bays with angled seabeds - which will make tsunami higher up. After 3 hours, waves of 20m high will hit the British Shetland Islands. After 2 hours, Denmark's Faeroe Islands will be submerged in waves of 14m high. After 6 hours, 6m high tsunamis will rip off the Scottish coast towards the coastal cities of England, Edinburgh and Dundee. The more you advance south, the weaker the wave. The fluctuations of the Nordic sea will act as a speed brake. The northern coastal cities of Germany were only flooded.

Computer models have warned a threat of lurking Europe. But computers can also be wrong?

Norway's Storegga frozen beach

Scientists have warned of the threat of tsunami threatening Europe

Tran Ngoc Dang