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Cited by 12Landslides and related hazardsCryospheric studies and observationsWinter Sports Injuries and Performance

The DOI matches its Crossref record; 34 of the 34 references it cites were found in a registry or an index; 13 of the 33 sources its claims cite were checked for support.

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

Open access
Gaume, Johan, Puzrin, Alexander M.·2021·Communications Earth & Environment
DOI 10.1038/s43247-020-00081-8
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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.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

The paper proposes a quantified slab-avalanche mechanism for the 1959 Dyatlov Pass incident: wind-transported snow accumulating above a cut made in the slope under a shoulder caused delayed release. Analytical and numerical models suggest a small slab could have caused severe but non-fatal thorax and skull injuries consistent with autopsy findings, while not explaining all mystery elements.

Key findings

  • A delayed slab release can occur when wind-deposited snow loads a variable-thickness slab above a cut; for the Dyatlov case, the analytical model with deposition flux \(Q = 0.008\ \mathrm{kg\ m^{-1}\ s^{-1}}\) gives delays of \(\Delta t_{\min}=7.2\ \mathrm{h}\) and \(\Delta t_{\max}=13.5\ \mathrm{h}\), overlapping the forensically estimated \(9.5\text{–}13.5\ \mathrm{h}\).
  • Critical wind-deposited snow heights are \(h_{w0,\min}=0.24\ \mathrm{m}\) and \(h_{w0,\max}=0.44\ \mathrm{m}\), with assumed weak-layer friction \(\varphi=20^\circ\), cohesion upper bound \(c \approx 440\ \mathrm{Pa}\), and a locally steeper weak-layer slope of \(\alpha=28^\circ\).
  • Material Point Method simulations predict slab impact velocity around \(2\ \mathrm{m/s}\); snow blocks of \(0.125\text{–}0.5\ \mathrm{m^3}\) and density \(400\ \mathrm{kg/m^3}\) produce maximum thorax deformation of \(28\%\text{–}34\%\), corresponding to moderate-to-severe non-fatal thoracic injuries on the Abbreviated Injury Scale.
  • The predicted tensile failure length is \(5.0\ \mathrm{m}\), with a tension crack at \(l_t = l_{cw} = 4.95\ \mathrm{m}\) and failed slab width \(B = 8.8\ \mathrm{m}\); the simulated avalanche filled the excavated space but had no significant runout, consistent with the reported lack of clear avalanche signs.

Methods

  • Analytical plane-strain model of a variable-thickness cohesive snow slab over a weak layer, loaded by wind-transported snow with sintering; it derives the release condition and bounds on delay for parameters including \(\alpha=28^\circ\), \(h_0=0.5\ \mathrm{m}\), \(h_c=0.1\ \mathrm{m}\), and \(l_c=4\ \mathrm{m}\).
  • Numerical simulations use the Material Point Method with finite-strain elastoplasticity and a Cohesive Cam Clay constitutive model for snow; a 2D avalanche simulation evaluates slab dynamics, and 3D simulations model impacts of snow blocks on a human thorax calibrated against automotive crash-test data from Kroell et al.
  • Inputs include forensic estimates of death timing, nearby weather-station wind data, autopsy/investigation reports, and published snow friction data; the human body is modeled as a hyperelastic solid with properties chosen to match thorax impact tests.

Limitations

  • The paper states that the analytical model assumes brittle weak-layer behavior, neglects the process zone and weak-layer volumetric collapse, uses a 2D geometry, and simplifies the deposited-snow profile; wind deposition flux versus wind velocity is an important uncertainty, though back-calculated wind velocities agree with nearby weather stations.
  • The paper states that the numerical models do not analyze the skeleton or individual ribs, initiate the MPM simulation at slab release without explicitly modeling the weak layer, and that thorax deformation is sensitive to disintegrated slab-block size and body positions; it also notes an alternative possibility that thorax injuries resulted from later snow impact in a ravine.
  • The paper states that it does not explain other controversial elements such as radioactivity traces, hiker behavior after leaving the tent, or body locations and states; evident from the text, the work is a case-specific backcalculation rather than a general validation across other avalanche incidents.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1038/s43247-020-00081-8

Cites

34 of 34 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

13 of 33 cited sources checked · 7 supported · 2 flagged · accuracy not yet measured

  • Premisecitation

    Buried crystals of depth hoar reported on the site tend to exhibit rather low friction values.

    “the buried crystals of depth hoar, which were reported by the investigation on the site (see Supplementary Note 3), tend to exhibit rather low friction values 13”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [13] van Herwijnen, A., & Heierli, J. Measurement of crack‐face friction in collapsed weak snow layers. Geophys. Res. Lett. 36. https://doi.org/10.1029/2009GL040389 source

      The Discussion and Conclusion (§4, paragraph 16; page unavailable) says crack-face friction in collapsed weak layers is far from negligible and that the measured friction showed no dependence on weak-layer grain type. The Results (§3, paragraph 14) describe depth hoar as porous and low in cohesion, not low in friction. The paper therefore does not support singling out depth-hoar crystals as tending to have low friction. (LLM, conf=0.84)

      Checked by a reasoning model — may be wrong.

      Experimental — accuracy not yet measured
  • Premisecitation

    The deposition flux Q = 0.008 kg m^-1 s^-1 requires average wind velocities in the range of 2-12 m/s.

    “Extensive research on snow accumulation shows 15 that this deposition flux requires average wind velocities in the range of 2-12 m s -1”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [15] Sturm, M. & Stuefer, S. Wind-blown flux rates derived from drifts at arctic snow fences. J. Glaciol. 59, 21–34 (2013). source

      The Discussion (page unavailable) says the authors excluded wind-speed data below 5 m/s from their flux equations because those data were contradictory; it also says that most snow will not be transported even at 4–5 m/s. The Conclusions (page unavailable) state that flux is not a single-valued function of wind speed. These passages run contrary to the asserted required range of 2–12 m/s for Q = 0.008 kg m⁻¹ s⁻¹. (LLM, conf=0.84)

      Checked by a reasoning model — may be wrong.

      Experimental — accuracy not yet measured
  • Premisecitation

    The critical slope angle can be as low as 20°, provided the dynamic friction angle of the snow is sufficiently low.

    “the critical slope angle can be as low 11 as 20° (Fig. 2b), provided the dynamic friction angle (sometimes called crack-face friction 11 ) of the snow is sufficiently low.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [11] Vontobel, I., Harvey, S. & Purves, R. S. In (eds Naaim-Bouvet, F., Durand, Y. & Lambert, R.) Terrain analysis of skier-triggered avalanche starting zones. In Proc. International Snow Science Workshop ISSW, Grenoble, France, 7–11 October 2013 (Montana State University, Bozeman, USA 2013).

      Section 3.2 (page unavailable) reports observed gradients in avalanche starting zones, but does not give a 20° critical slope angle or relate it to snow friction. Searches for “dynamic friction angle,” “crack-face friction,” and “20° critical slope angle” found no passage addressing that relationship. (LLM, conf=0.73)

      Experimental — accuracy not yet measured
  • Interpretationcitation

    In the absence of significant snowfall, the only way to accumulate additional load is through wind transport.

    “In the absence of significant snowfall, the only way to accumulate additional load is through wind transport 15 .”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [15] Sturm, M. & Stuefer, S. Wind-blown flux rates derived from drifts at arctic snow fences. J. Glaciol. 59, 21–34 (2013). source
  • Premisecitation

    Partial snow sintering leads to strengthening of the wind-transported snow layer.

    “partial snow sintering 16 leads to strengthening of the wind-transported snow layer.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [16] Podolskiy, E. A., et al. Healing of snow surface-to-surface contacts by isothermal sintering. Cryosphere 8, https://doi.org/10.5194/tc-8-1651-2014 (2014). source

      The Conclusions report that sintering healed snow interfaces and increased their strength in laboratory tests. The paper does not establish that partial sintering strengthens a wind-transported snow layer specifically; its Limitations section cautions against directly projecting results from artificially created interfaces onto real snow layers. Page numbers were not provided in our copy. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
  • It may state two separate claims as one. 19
  • Probably not a substantial claim. 12
  • The quote only partly states this claim. 2

  • It may state two separate claims as one.

    Premisecitation

    Extensive research on snow accumulation shows that this deposition flux requires average wind velocities in the range of 2-12 m/s, in agreement with data from nearby weather stations on the night of the accident.

    “Extensive research on snow accumulation shows 15 that this deposition flux requires average wind velocities in the range of 2-12 m s -1 which is in agreement with data from nearby weather stations on the night of the accident (see Supplementary Note 3).”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [15] Sturm, M. & Stuefer, S. Wind-blown flux rates derived from drifts at arctic snow fences. J. Glaciol. 59, 21–34 (2013). source

      The Analysis section (page unavailable) relates measured snow-deposition fluxes to mean wind speeds, so the paper supports a relationship between them. It does not establish that the cited flux requires average winds of 2–12 m/s: the Discussion says flux varies widely at a given speed and that data below 5 m/s are contradictory. The comparison with weather-station data on the night of the accident is not a finding of this paper. (LLM, conf=0.87)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim.

    Premisecitation

    For the Dyatlov case, a reasonable value of friction in the weak layer is φ = 20°.

    “A reasonable value of the friction in the weak layer 20 (see Supplementary Note 6) is φ ¼ 20 .”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [20] Reiweger, I., Gaume, J. & Schweizer, J. A new mixed‐mode failure criterion for weak snowpack layers. Geophys. Res. Lett. 42, 1427–1432 (2015). source
    • cites Supplementary Note 6

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim.

    Premisecitation

    Recent work on delayed snow avalanches proposed a release mechanism driven by rate-dependent processes in the snow slab and weak layer, which can develop under constant loads.

    “Recent work on delayed snow avalanches 14 has proposed a release mechanism driven by rate-dependent processes in the snow slab and the weak layer 10 , which can develop under constant loads.”
    Quote in the paperSubstantial claim2 of 2 sources checked
    • cites [14] Puzrin, A. M., Faug, T. & Einav, I. The mechanism of delayed release in earthquake-induced avalanches. Proc. R. Soc. A 475, 20190092 (2019). source
    • cites [10] Schweizer, J., Bruce Jamieson, J., & Schneebeli, M. Snow avalanche formation. Rev. Geophys. 41. https://doi.org/10.1029/2002RG000123 (2003) source

  • It may state two separate claims as one.

    Findingown data

    Three-dimensional numerical simulations based on the Material Point Method and finite-strain elastoplasticity show that the small-slab avalanche impacted the hikers lying on the tent floor and filled the excavated space but did not have a significant runout, consistent with the reported lack of clear avalanche signs.

    “Three-dimensional numerical simulations based on the Material Point Method (MPM) and finite-strain elastoplasticity 19 (see Methods) show that this small-slab avalanche impacted the hikers lying on the tent floor and filled the excavated space but did not have a significant runout, consistent with the reported lack of clear avalanche signs (Fig. 5).”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [19] Gaume, J., Gast, T., Teran, J., van Herwijnen, A. & Jiang, C. Dynamic anticrack propagation in snow. Nat. Commun. 9, 1–10 (2018). source

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    The APIC method used for transfer between grid and particles allows exact conservation of momentum and angular momentum.

    “Here we used the Affine Particle In Cell (APIC) method for the transfer between grid and particles 36 which allows an exact conservation of momentum and angular momentum.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [36] Jiang, C., Schroeder, C. & Teran, J. An angular momentum conserving affine-particle-in-cell method. J. Comput. Phys. 338, 137–164 (2017). source

  • It may state two separate claims as one.

    Interpretationcitation

    The calculated B = 8.8 m is consistent with observed B/l_t ratios and comparable to the width of the cut b = 6.5-7.5 m.

    “consistent with the observed B=l t ratios 34 and comparable to the width of the cut b=6.5-7.5 m (for a 4.5 m long tent, the cut had to be around 1.0-1.5 m longer on each side).”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [34] McClung, D. M. Dimensions of dry snow slab avalanches from field measurements. J. Geophys. Res.: Earth Surf. 114. https://doi.org/10.1029/2007JF000941 (2009). source

  • It may state two separate claims as one.

    Findingown data

    At this velocity, an impact on a human thorax of a typical snow block with volume 0.125-0.5 m3 and density 400 kg/m3 results in maximum thorax deformation between 28% and 34%, corresponding to the lower range of values reported from crash tests by Kroell et al. for a 10 kg mass impacting the thorax at 7 m/s.

    “At this velocity, an impact on a human thorax of a typical snow block with a volume of 0.125-0.5 m 3 and density 400 kg/m 3 results in a maximum thorax deformation between 28% and 34%, corresponding to the lower range of values reported from crash tests by Kroell et al. 18 for a 10 kg mass impacting the thorax at a speed of 7 m/s”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [18] Kroell, C. K., Schneider, D. C., & Nahum, A. M. Impact tolerance and response of the human thorax II (No. 741187). SAE Technical Paper. https://doi.org/10.4271/741187 (1974) source

  • It may state two separate claims as one.

    Findingreasoning

    The growth of l_cw is affected by the gradual increase of the slab thickness and continues until the shear stress in the weak layer reaches the peak shear strength τp near the cut.

    “Hence, the growth of l cw is affected by the gradual increase of the slab thickness, and continues until the shear stress in the weak layer reaches the peak shear strength τ p in the vicinity of the cut (Fig. 3b).”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The weak layer exhibits brittle behavior, allowing the effects of the process zone to be neglected.
    • The authors state this as an assumption: Weak layer volumetric collapse did not need to be accounted for because the layer remains completely intact before the onset of instability.
    • The authors state this as an assumption: The analytical model assumes a 2D geometry.
    • The authors state this as an assumption: The 2D profile of the deposited snow has been simplified for the sake of obtaining a closed-form solution.
    • The authors state this as an assumption: The surface of the new snow layer can be described by a parabolic function.
    • The authors state this as an assumption: The shear response of the weak layer is linear.
    • The authors state this as an assumption: Extension in the snow slab is linear.

  • It may state two separate claims as one.

    Findingreasoning

    Further snow deposition does not mobilize additional shear resistance in the weak layer; instead it initiates rapid softening close to the cut, resulting in loss of equilibrium, dynamic uphill growth of the basal shear fracture, and slab release.

    “A further snow deposition does not mobilize additional shear resistance in the weak layer; in contrast, it initiates rapid softening of the weak layer close to the cut, resulting in the loss of equilibrium, dynamic uphill growth of the basal shear fracture, and slab release.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The weak layer exhibits brittle behavior, allowing the effects of the process zone to be neglected.
    • The authors state this as an assumption: Weak layer volumetric collapse did not need to be accounted for because the layer remains completely intact before the onset of instability.
    • The authors state this as an assumption: The analytical model assumes a 2D geometry.
    • The authors state this as an assumption: The 2D profile of the deposited snow has been simplified for the sake of obtaining a closed-form solution.
    • The authors state this as an assumption: The surface of the new snow layer can be described by a parabolic function.
    • The authors state this as an assumption: The shear response of the weak layer is linear.
    • The authors state this as an assumption: Extension in the snow slab is linear.

  • It may state two separate claims as one.

    Findingcitation

    The slope consists of 4-6 m high steps and the tent was installed below one of them.

    “This slope consists of 4-6 m high steps 1 (Fig. 1c and Fig. SF2) and the tent was installed below one of them”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [1] Buyanov, E. V. and Slobtsov, B. E. Mystery of the Dyatlov Group Death (Taina Gibeli Gruppy Dyatlova). Litres (2014) ISBN 978-5040256921.

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • It may state two separate claims as one.

    Findingown data

    The high-resolution 2D avalanche simulation evaluated snow slab impact velocity up to 2 m/s and typical snow block dimensions up to 0.5 m^3.

    “Next, we perform a high-resolution 2D avalanche simulation using the main features known about the Dyatlov tent configuration (Fig. 1) so as to evaluate the snow slab impact velocity (up to 2 m/s, see Supplementary Note 5 and Supplementary Movie 2) and the range of typical snow block dimensions (up to 0.5 m 3 , see Supplementary Note 5 and Supplementary Movies 4-6).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Supplementary Note 5

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Supplementary Movie 2

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Supplementary Movies 4-6

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • It may state two separate claims as one.

    Findingreasoning

    For the Dyatlov case, h_w0,min = 0.24 m and h_w0,max = 0.44 m.

    “from Eqs. ( 37)-(40) we obtain h w0; min ¼ 0:24 m; h w0; max ¼ 0:44 m:”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: After the slope is cut, behavior in the weak layer is linear elastic, with the shear stress not yet reaching the peak strength.
    • The authors state this as an assumption: The straight portion of the slope can be neglected and the whole slab within 0 ≤ x ≤ L0 can be assumed parabolic.
    • The authors state this as an assumption: The contribution of the wind-transported snow to side resistance can be neglected, and the slab is thinning at the sides to h_c.

  • It may state two separate claims as one.

    Findingreasoning

    For the Dyatlov case, with deposition mass flux Q = 0.008 kg m^-1 s^-1, Δt_min = 7.2 h and Δt_max = 13.5 h.

    “By adjusting the deposition mass flux to Q ¼ 0:008 kg m À1 s À1 , from Eqs. (36) and (41) we determine Δt min ¼ 7:2 h; Δt max ¼ 13:5 h;”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: After the slope is cut, behavior in the weak layer is linear elastic, with the shear stress not yet reaching the peak strength.
    • The authors state this as an assumption: The straight portion of the slope can be neglected and the whole slab within 0 ≤ x ≤ L0 can be assumed parabolic.
    • The authors state this as an assumption: The contribution of the wind-transported snow to side resistance can be neglected, and the slab is thinning at the sides to h_c.

  • Probably not a substantial claim. The paper may give no reason why it holds. It may state two separate claims as one.

    Premisenone given

    No mechanism similar to the one inspired by the Dyatlov mystery has been explored in the literature, and its physical quantification required new theoretical developments.

    “Nevertheless, no mechanism similar to the one inspired by the Dyatlov mystery has been explored in the literature, and its physical quantification required new theoretical developments.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Study design and conductown data

    Both the analytical and numerical models independently predicted a similar size of the failed slab, providing additional validation for the new mechanism.

    “In spite of these simplifications, both the analytical and numerical models independently predicted a similar size of the failed slab, providing additional validation for the new mechanism.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.

    Interpretationreasoning

    Possible construction of a small snow parapet by the Dyatlov group could contribute to additional loading.

    “Possible construction of a small snow parapet by the Dyatlov group (classical safety measure for snow camping, Fig. SF3), could contribute to additional loading.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    A combination of irregular topography, a cut made in the slope to install the tent, and 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.

    “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.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper may give no reason why it holds.

    Premisenone given

    Such injuries are not usually observed in avalanche victims because impacts rarely occur against stiff obstacles.

    “Such injuries are not usually observed in avalanche victims, because impacts rarely occur against stiff obstacles.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Interpretationreasoning

    Given this uncertainty, it is also possible that the thorax injuries were the result of a later snow impact in a very steep ravine where the bodies of the victims, escaping the avalanche area, were found.

    “Given this uncertainty, it is also possible 1 that the thorax injuries were the result of a later snow impact in a very steep ravine where the bodies of the victims, escaping the avalanche area, were found.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [1] Buyanov, E. V. and Slobtsov, B. E. Mystery of the Dyatlov Group Death (Taina Gibeli Gruppy Dyatlova). Litres (2014) ISBN 978-5040256921.

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • It may state two separate claims as one.

    Interpretationreasoning

    The average slope of the buried weak layer was about 28°, increasing the probability of slab release.

    “It results in the average slope of the buried weak layer being about 28°, increasing the probability of slab release”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Premisecitation

    The originally popular avalanche theory for the Dyatlov Pass incident has been questioned because of contradictory evidence: no obvious avalanche signs, average slope angle lower than 30°, release at least nine hours after the cut, and thorax/skull injuries not typical for avalanche victims.

    “The originally popular avalanche theory has been questioned due to several contradictory pieces of evidence 1 : (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”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [1] Buyanov, E. V. and Slobtsov, B. E. Mystery of the Dyatlov Group Death (Taina Gibeli Gruppy Dyatlova). Litres (2014) ISBN 978-5040256921.

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • The quote only partly states this claim.

    Interpretationnone given

    The upward-thinning slab made it more difficult to trace avalanche signs, especially 26 days after the incident.

    “It makes it more difficult to trace avalanche signs, especially 26 days after the incident.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    Small scale topographic variability resulted in a locally steep weak snow layer while the larger shoulder contributed to significant wind-driven snow accumulation above the tent, eventually leading to an instability.

    “small scale topographic variability resulted in a locally steep weak snow layer while the larger shoulder contributed to significant wind-driven snow accumulation above the tent, eventually leading to an instability.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    Snow accumulation above the tent resulted from katabatic winds and the presence of a shoulder located above the tent.

    “Snow accumulation above the tent resulted from katabatic winds and the presence of a shoulder located above the tent (Fig. 2a).”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Interpretationcitation

    According to the Abbreviated Injury Scale, these deflections would mostly lead to non-fatal thoracic injuries from moderate to severe, in agreement with the autopsy report of the Dyatlov-incident criminal investigation.

    “According to the Abbreviated Injury Scale 18 (AIS), these deflections would mostly lead to non-fatal thoracic injuries from moderate to severe, in agreement with the autopsy report of the Dyatlov-incident criminal investigation.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [18] Kroell, C. K., Schneider, D. C., & Nahum, A. M. Impact tolerance and response of the human thorax II (No. 741187). SAE Technical Paper. https://doi.org/10.4271/741187 (1974) source

  • Probably not a substantial claim.

    Interpretationreasoning

    Building a tent even on a relatively mild slope, less than 30°, can be dangerous when combined with a cut in the slope.

    “This implies that building a tent even on a relatively mild slope (less than 30°) can be dangerous and should not be recommended when combined with a cut in the slope.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Interpretationcitation

    Possible construction of a parapet above the cut could have accelerated the failure process.

    “the possible construction of a parapet 1 above the cut (a classical safety procedure to protect the tent from the wind, Fig. SF3) could have accelerated the failure process.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [1] Buyanov, E. V. and Slobtsov, B. E. Mystery of the Dyatlov Group Death (Taina Gibeli Gruppy Dyatlova). Litres (2014) ISBN 978-5040256921.

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • It may state two separate claims as one.

    Interpretationreasoning

    Strong katabatic winds led to progressive snow accumulation due to the local topography, with the shoulder above the tent causing a delayed failure.

    “strong katabatic winds that led to progressive snow accumulation due to the local topography (shoulder above the tent) causing a delayed failure”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim.

    Study design and conductcitation

    Injury severity was determined by relating maximum normalized deflections to the Abbreviated Injury Scale (AIS) presented by Kroell et al.

    “Finally, the severity of injuries was determined by relating the maximum normalized deflections to the Abbreviated Injury Scale (AIS, see Supplementary Note 6) presented by Kroell et al. 18 .”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [18] Kroell, C. K., Schneider, D. C., & Nahum, A. M. Impact tolerance and response of the human thorax II (No. 741187). SAE Technical Paper. https://doi.org/10.4271/741187 (1974) source
    • cites Supplementary Note 6

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim.

    Premisenone given

    MPM is a hybrid Eulerian-Lagrangian method well suited to studying problems involving large deformations, collisions and fractures.

    “MPM is a hybrid Eulerian-Lagrangian method which is well suited to studying problems involving large deformations, collisions and fractures.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.

    Study design and conductnone given

    The use of cubic B-splines as shape functions guarantees continuity of gradients at the nodes.

    “In addition, we use cubic B-splines as shape functions which guarantees the continuity of the gradients at the nodes.”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Study design and conductcitation

    The model was calibrated by simulating a 10 kg rigid block impact and adjusting the elastic modulus of the body to reproduce the maximum normalized deflection of 0.49 that resulted in fatal injuries.

    “In order to calibrate our model, we first simulate the impact of a 10 kg rigid block (0.15 × 0.15 × 0.06 m) moving with velocity 7 m/s on a 3D human thorax with restrained back (see Supplementary Note 5 and Supplementary Movie 3).This setup corresponds to the automotive crash experiments performed by Kroell et al. 18 .We adjust the elastic modulus of the body in order to reproduce the same maximum”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [18] Kroell, C. K., Schneider, D. C., & Nahum, A. M. Impact tolerance and response of the human thorax II (No. 741187). SAE Technical Paper. https://doi.org/10.4271/741187 (1974) source
32 of 32

  • The authors state this as an assumption.

    The weak layer exhibits brittle behavior, allowing the effects of the process zone to be neglected.

    “given the very low reported temperatures, we assumed a brittle behavior for the weak layer which allows neglecting the effects of the process zone 30 .”

  • The authors state this as an assumption.

    Weak layer volumetric collapse did not need to be accounted for because the layer remains completely intact before the onset of instability.

    “Moreover, weak layer volumetric collapse 19,22,23 did not have to be accounted for in our approach because this layer remains completely intact before the onset of instability.”

  • The authors state this as an assumption.

    The analytical model assumes a 2D geometry.

    “Furthermore, the analytical model assumes a 2D geometry which in this case can be justified by the fact that the length of the shoulder controlling snow deposition is much larger than the length of the tent.”

  • The authors state this as an assumption.

    The 2D profile of the deposited snow has been simplified for the sake of obtaining a closed-form solution.

    “Yet, the 2D profile of the deposited snow has been simplified for the sake of obtaining a closed-form solution.”

  • The authors state this as an assumption.

    The surface of the new snow layer can be described by a parabolic function.

    “Assuming that the surface of the new snow layer can also be described by a parabolic function, the thickness of the wind-transported snow is”

  • The authors state this as an assumption.

    The shear response of the weak layer is linear.

    “The shear response of the weak layer is assumed to be linear:”

  • The authors state this as an assumption.

    Extension in the snow slab is linear.

    “Extension in the snow slab is also assumed to be linear:”

  • The authors state this as an assumption.

    After the slope is cut, behavior in the weak layer is linear elastic, with the shear stress not yet reaching the peak strength.

    “It is assumed that after the slope is cut, behavior in the weak layer is linear elastic, with the shear stress τ in Fig. 3b not yet reaching the peak strength τ p .”

  • The authors state this as an assumption.

    The straight portion of the slope can be neglected and the whole slab within 0 ≤ x ≤ L0 can be assumed parabolic.

    “In this and the following sections we neglect the straight portion of the slope and assume that within 0 ≤ x ≤ L 0 the whole slab is parabolic.”

  • The paper relies on this without support.

    For h_c/h_0 ≤ 0.2, the parabolic simplification has a negligible effect on the solution.

    “It can be shown that for h c =h 0 ≤ 0:2 (consistent with the Dyatlov case), this simplification has a negligible effect on the solution.”

  • The authors state this as an assumption.

    The contribution of the wind-transported snow to side resistance can be neglected, and the slab is thinning at the sides to h_c.

    “It is assumed that the contribution of the wind-transported snow to side resistance can be neglected, and the slab is thinning at the sides to h c .”
11 of 11

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Different minimum predicted delays

    Minor

    The overview gives a minimum predicted delay of 7.5 h, whereas the Methods calculate a minimum of 7.2 h. Both refer to the model's lower bound for delayed release.

1 of 1

Citations

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. McCloskey, K. Mountain of the Dead: The Dyatlov Pass Incident (The History Press Ltd, 2013).

Cited by

Sorted by citations

Related

Metadata

Authors
Gaume, J., & Puzrin, A. M.
Affiliations
  • WSL Institute for Snow and Avalanche Research SLF (CH)
  • ETH Zurich (CH)
Corresponding author
Puzrin, Alexander M.
ORCID
Venue
Communications Earth & Environment
Publisher
Springer Science and Business Media LLC
Published
2021-01-28
Volume
2
Issue
1
ISSN
2662-4435 (ISSN-L)
DOI
10.1038/s43247-020-00081-8
OpenAlex
W3122208000
Semantic Scholar
0fb5b59d18ac6d6479ec21b02f187f01cbe2b40e
Cited by
12
References
33
Citations by year
2026: 1 · 2025: 3 · 2024: 3 · 2023: 3 · 2022: 2
FWCI
2.02
Type
journal article
Language
en
Open access
Licence
Locations
  • Communications Earth & Environment (publishedVersion, cc-by)
  • DORA WSL (Swiss Federal Institute for Forest, Snow and Landscape Research) (submittedVersion, cc-by)
  • Infoscience (Ecole Polytechnique Fédérale de Lausanne) (submittedVersion, cc-by-nc-nd)
  • Repository for Publications and Research Data (ETH Zurich) (submittedVersion, cc-by)
  • ETH Zürich Research Collection (cc-by)
Funders
  • National Science Foundation
  • University of Pennsylvania
  • WSL-Institut für Schnee- und Lawinenforschung SLF
  • Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (168998, 181227)
  • University of Sydney
Topics
  • Physical Sciences › Environmental Science › Management, Monitoring, Policy and Law › Landslides and related hazards
  • Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Cryospheric studies and observations
  • Health Sciences › Medicine › Orthopedics and Sports Medicine › Winter Sports Injuries and Performance
Keywords
slab avalanches, wind-blown snow, katabatic winds, irregular topography, slope cut, snow deposition

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

A language model drew the claims from the paper on 2026-10-29, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).

A second model labelled each claim on 2026-10-29 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).

Cited sources are checked with a language model’s help (gpt-6-sol).

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

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