Dyatlov Pass - A Slab Avalanche ?

Anyone can post and discuss breaking science news or science-related public policy, that interests them (please respect posting guidelines and be sure to reference properly).
Forum rules
Please be sure to check our forum's Rules & Guidelines

Dyatlov Pass - A Slab Avalanche ?

Postby toucana on January 31st, 2021, 2:34 pm 

Image

A view of the tent the adventurers stayed in as the rescuers found it on Feb. 26, 1959. The tent had been cut open from inside, and most of the skiers had fled in socks or barefoot.


A new study by scientists at the Swiss Federal Institute of Technology (EPFL) has provided a fresh insight into a mystery that became known as the Dyatlov Pass Incident (Russian: гибель тургруппы Дятлова) which happened over 60 years ago in a remote part of the Ural mountains in the Soviet Union.

https://arstechnica.com/science/2021/01/9-russian-adventurers-mysteriously-froze-to-death-a-new-theory-explains-why/

In January 1959 a group of experienced young cross-country skiers from the Ural Polytechnic Institute set out from Sverdlosk (Yekaterinburg) on an 220 mile trek to Mount Orteten whose name means ‘Don’t Go There’ in the local Mansi language. The party led by engineering student Igor Dyatlov consisted of eight men and two women. The expedition began on 25 January 1959. One member of the party was taken ill and turned back on the 28th. The remaining nine hikers continued the trek.

The party failed to establish contact again by a previously agreed date of 12 February, and a search began on 20th February. A badly damaged tent was found at an abandoned campsite on Kholat Syakhi or ‘Dead Mountain’ on 26 February. Five bodies were found in various locations within a 1.5Km radius of the campsite. It took another two months to find the bodies of the other four travellers which were buried under four metres of snow in a ravine.

The search party were deeply perplexed by what they found. The badly damaged tent appeared to have been cut open from the inside. The tongue and eyes of two victims were missing, and several others - all young and fit - had fractured skulls and smashed ribs. Most of them had apparently fled in a sudden panic into a sub-zero arctic night wearing only socks and underwear. Two had apparently tried to climb trees, some had tried to light a fire, and three had subsequently died while trying to crawl back to their campsite.

In the absence of any sensible explanation, conspiracy theories began to proliferate. An attack by a Yeti, secret weapons testing by the Red Army, or a homicidal attack by local Mansi tribesman were all suggested at various times.

The most recent Swiss study however suggests that the culprit may well have been a rare type of snow event known as a slab avalanche. On the basis of computer modelling, scientists now believe that when the expedition set up their campsite they cut into a ledge in the snow-covered hillside to provide a level surface on which to pitch their tent. In doing so they disturbed the relationship between the surface snow slab and a weak layer of finer crystal snow beneath it. During the night, strong katabatic winds blowing down the mountainside scooped and piled extra snow on top of the slap overhanging the tent, until a slipping point was reached and a severe but localised slab avalanche smashed into the tent crushing the sleepers against the skis they had laid under the tent as a floor.

The search party which first discovered the tent didn’t consider an avalanche as a possible explanation because there was no evidence of fresh snowfall. The tent was not heavily buried in snow, and most significantly, the slope of the hillside was at an incline of only 23 degrees - well below the 30 degree threshold normally considered necessary for an avalanche. The peculiar injuries found on the victims didn’t appear to be consistent with those normally sustained in avalanches either.

The new study by the Swiss scientific team answers all of these points. Computer modelling of slab avalanches show that they can form on inclines of little more than 20 degrees. They are capable of producing intensely localised, but quite violent snow falls. Data based on human cadaver studies dating from the 1970s also suggest that slab avalanches can inflict the type of injuries seen in the Dyatlov Pass victims.


footnote - The site of the accident was renamed as Dyatlov Pass in memory of the expedition leader Igor Dyatlov. A detailed photo-journalistic account of the mystery was published by the BBC in 2019

https://www.bbc.co.uk/news/extra/SoLiOdJyCK/mystery_of_dyatlov_pass
User avatar
toucana
Chatroom Operator
 
Posts: 1979
Joined: 20 Sep 2006
Location: Bristol UK
Blog: View Blog (10)


Return to Science News Discussion Forum

Who is online

Users browsing this forum: No registered users and 17 guests

cron