SOURCE: New Scientist
DATE: July 11, 2017
SNIP: Earthquakes in Greenland are rare. At least, they’re supposed to be. But a few weeks ago, a 4.1 “quake” struck Nuugaatsiaq, a tiny island off Greenland’s west coast, triggering a massive tsunami that smashed homes, leaving at least four people dead.
But what residents – and seismic equipment – initially labelled a quake may be nothing of the sort.
“Everyone was fooled by the collapse of a mountain,” says Martin Luethi, a Swiss glaciologist who has been studying Greenland’s glaciers since 1995. “The tsunami wasn’t triggered by an earthquake.”
Luethi believes the culprit was a landslide at nearby Karrat fjord. And as the falling mountain hit the ocean, it created enough seismic noise to dupe sensors and generate the waves that inundated Nuugaatsiaq.
That’s why there’s such a powder keg brewing, Luethi says. The landslide in Nuugaatsiaq was reportedly 1000 metres in length and 300 metres wide. And while the ensuing tsunami was disastrous, it’s shifting focus from the real problem: this wasn’t a one-off. This region is full of craggy fjords undergoing temporal shift. Meaning more so-called quakes – and accompanying tsunamis – seem imminent.