Arctic mega-tsunami caused by landslide, not a quake
Digital Reporter
Tuesday, August 1, 2017, 6:56 PM - Recent research into a June tsunami on the west coast of Greenland says the event, which killed four people, was actually caused by a massive landslide about 20 km away.
On June 17, substantial amounts of rock from the Karrat Fjord plunged into the sea, causing water to raise to at least 90 m (300 ft.) at the coast of the shallow inlet. By the time the wave travelled across the bay into the village of Nuugaatsiaq, it was about 40 m high. The water washed away 11 homes and caused significant damage to others. The fjord is composed mainly of rock and ice.
KEEP ON TOP OF ACTIVE WEATHER: Georgia Institute of Technology engineer Hermann Fitz led a team of researchers that recently returned from a trip to the site of the landslide. The team hoped to gather data that would help them design a 3D model of the landslide, in order to better understand its origins.
Image courtesy of Hermann Fitz. Tsunami damaged home Nuuqaatsiaq, Greenland.
According to their research, there is a chance that another landslide could occur nearby, which is why three villages remain evacuated.
Fitz said that the waves would have moved “about the length of a football field every second”, and would have reached the town in about five minutes.
Image courtesy of Hermann Fritz - "The right half of the highlighted area shows the scarred hillside in Greenland's Karrat Fjord after a landslide fell a kilometer (about 3,300 feet) into the water below, causing a tsunami."
Trine Dahl-Jensen, a seismologist at the geological Survey of Denmark and Finland, told Nature that the slide was so significant that it originally registered as a magnitude-4.1 earthquake.
Most tsunamis are caused by seismic energy resulting from a submarine earthquake. Tsunamis that are caused by landslides displace more water and therefore often create more damage.
“Landslide-generated tsunamis are much more locally limited that tsunamis produce by sea quakes, but they can massively tall and devastating in the vicinity,” Fitz told Nature.
Source: Georgia Tech School of Civil and Environmental Engineering | Nature | Geoscience Australia | Geology All images courtesy of Georgia Tech School of Civil Engineering and Hermann Fitz
