Explanation of the Dyatlov Pass Mystery & What Killed the Hikers?

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28 January 2021
Mechanisms of slab avalanche release and impact in the Dyatlov Pass incident in 1959

Abstract
The Dyatlov Pass incident is an intriguing unsolved mystery from the last century. In February 1959, a group of nine experienced Russian mountaineers perished during a difficult expedition in the northern Urals.

A snow avalanche hypothesis was proposed, among other theories, but was found to be inconsistent with the evidence of a lower-than-usual slope angle, scarcity of avalanche signs, uncertainties about the trigger mechanism, and abnormal injuries of the victims.

The challenge of explaining these observations has led us to a physical mechanism for a slab avalanche caused by progressive wind-blown snow accumulation on the slope above the hikers’ tent.

Here we show how a combination of irregular topography, a cut made in the slope to install the tent and the subsequent deposition of snow induced by strong katabatic winds contributed after a suitable time to the slab release, which caused severe non-fatal injuries, in agreement with the autopsy results.

Introduction
During the night of February 1, 1959, nine Russian hikers died under unexplained circumstances during a skiing expedition in the northern Ural Mountains.

The group had decided to set up their camp on the slope of the Kholat Saykhl; the name means “Dead Mountain” in the local Mansi language.

Something unexpected happened after midnight that caused expedition members to cut the tent suddenly from the inside and escape towards a forest, more than 1 km down slope without appropriate clothes, under extremely low temperatures and in the presence of strong katabatic winds induced by the passing of an arctic cold front.

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Twenty-six days to three months after the tragedy, search teams found bodies in the forest and on their way back to the tent.

According to the 1959 Soviet criminal investigation, “a compelling natural force” led to the death of the Dyatlov group. However, the nature of this force has not been identified. The mystery arises from numerous unexplained observations.

While hypothermia was determined to be the main cause of death, four hikers had severe thorax or skull injuries, two were found with missing eyes and one without tongue; some were almost naked and barefoot, traces of radioactivity were found on some of their clothes, and signs of glowing orange spheres floating in the sky were reported that night,

Several theories have been proposed to explain this incident, including infrasound-induced panic, animals, attacks by Yetis or local tribesmen, katabatic winds, a snow avalanche, a romantic dispute, nuclear-weapons tests, etc.

The originally popular avalanche theory has been questioned due to several contradictory pieces of evidence1: (1) no obvious signs of an avalanche or debris were reported by the search team that arrived 26 days later, (2) the average slope angle above the tent location was not sufficiently steep for an avalanche (lower than 30°), (3) the hypothetical avalanche released during the night, at least nine hours after the cut was made in the slope, and (4) the thorax and skull injuries were not typical for avalanche victims.

In 2015, the Investigative Committee of the Russian Federation (ICRF) re-opened the investigation and in 2019 concluded that a snow avalanche was the most probable cause of the accident.

The results of this investigation have been challenged recently by the office of the Prosecutor General of the Russian Federation, who in 2019 started its own investigation and in July 2020 came to the same conclusion as ICRF.

Both investigations have not, however, disclosed scientific explanations for the four counterarguments listed above and therefore keep being challenged by the relatives, public, and researchers. In particular, a 2019 Swedish-Russian expedition disagreed with the ICRF conclusions, instead proposing that the direct impact of katabatic winds on the tent was the main contributing factor.

Based on the significant amount of published material1,2,3,4,5,6,7,8,9, it seems that previous investigations lack an important ingredient: a quantifiable physical mechanism that can reconcile the avalanche hypothesis with seemingly conflicting evidence.

Identifying such a mechanism may provide new insights into the nature of storm-triggered snow pack instabilities, which is another important motivation for this work. . .

Conditions for a delayed avalanche. . .

. . . our work may contribute to determining the plausibility of the avalanche hypothesis.

In conclusion, our work shows the plausibility of a rather rare type of snow slab instabilities that could possibly explain the Dyatlov Pass incident.

Yet, we do not explain nor address other controversial elements surrounding the investigation such as traces of radioactivity found on the victims’ garments, the behavior of the hikers after leaving the tent, locations and states of bodies, etc. . .

Last Edited by NotStarvingActress on 02/02/2021 10:40 AM