By Cheyenne MacDonald

A devastating mega-tsunami tore through a remote area of Greenland in June, destroying homes as huge waves carrying the shattered chunks of a glacier swept through.

Now, data from a reconnaissance mission at the site has revealed the terrifying waves reached more than 90m tall - and scientists say they were caused by a massive landslide.

The landslide that gave rise to the disaster plunged into the ocean from roughly 1000m up the Karrat Fjord, spurring a small earthquake and tsunami waves that travelled about the length of a football field each second, according to theDaily Mail.

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Scientists from the Georgia Institute of Technology say this is a 'particularly unique situation,' as another landslide nearby is active, but has yet to fall. Photo / Georgia Institute of Technology
Scientists from the Georgia Institute of Technology say this is a 'particularly unique situation,' as another landslide nearby is active, but has yet to fall. Photo / Georgia Institute of Technology

Scientists from the Georgia Institute of Technology say this is a "particularly unique situation", and another landslide nearby is active, but has yet to fall.

During the June tsunami, houses were destroyed and four people were washed away.

Three villages are still evacuated.

"The second adjacent landslide remains a hazard, with an open back scarp and wide cracks 1000m above the water," said Georgia Tech professor Hermann Fritz.

"We had an unusual opportunity to record the aftermath of one landslide and tsunami and the baseline of a potential future event."

The team, including a volcanologist from the University of Oregon and a geotechnical engineer from BGC Engineering, are at the site to collect data and build a 3D reconstruction of the landslide.

This revealed that the massive waves generated by the landslide climbed more than 90m on the same side of the coastline, and 50m in the region directly across.

According to the experts, the waves on both sides far surpassed the height - also known as runup - from the 2011 tsunami in Japan, which hit about 40m.

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These waves first began at staggering heights, and then quickly dissipated as they traveled across the fjord.

The waves sent huge icebergs hurtling ashore - but, the researchers say these are already shrinking. Photo / Georgia Institute of Technology
The waves sent huge icebergs hurtling ashore - but, the researchers say these are already shrinking. Photo / Georgia Institute of Technology

"The essentially undisturbed semi-circle spreading of the tsunami waves results in massive decay of the surveyed tsunami runup heights compared to the initial tsunami height," Fritz said.

The waves sent huge icebergs hurtling ashore, but the researchers say they are already shrinking.

The team is hoping to study this debris to find out more about the full extent of the disaster, and better understand why four people were swept out to sea while others were not, and were even able to record footage of the waves as they rolled in.

Although the exact cause of the tsunami first eluded authorities, the videos from the Danish Navy and other responders provided useful insight, revealing scarring that stretched a full kilometre up the slopes of the fjord.

This indicates that a landslide was to blame for the devastating waves, which have been compared to a 1958 landslide-generated tsunami in Lituya Bay, Alaska.

But last month's waves may have been even more extreme because the landslide fell into deeper water and a larger fjord system.

"At these depths, tsunami waves travel about the length of a football field every second, so the tsunami wave arrived very fast - probably in the order of five minutes for this village 30km away," Fritz said.

"That left very little time to react.

"The combination of a small earthquake from the plunge of the landslide, the sound, and unusual motion in the fjord prompted a spontaneous self-evacuation."