Abstract
The Chaos Canyon landslide, which collapsed on the afternoon of 28 June 2022 in Rocky Mountain National Park, presents an opportunity to evaluate instabilities within alpine regions faced with a warming and dynamic climate. Video documentation of the landslide was captured by several eyewitnesses and motivated a rapid field campaign. Initial estimates put the failure area at 66 630 m2, with an average elevation of 3555 m above sea level. We undertook an investigation of previous movement of this landslide, measured the volume of material involved, evaluated the potential presence of interstitial ice and snow within the failed deposit, and examined potential climatological impacts on the collapse of the slope. Satellite radar and optical measurements were used to calculate deformation of the landslide in the 5 years leading up to collapse. From 2017 to 2019, the landslide moved ∼ 5 m yr−1, accelerating to 17 m yr−1 in 2019. Movement took place through both internal deformation and basal sliding. Climate analysis reveals that the collapse took place during peak snowmelt, and 2022 followed 10 years of higher than average positive degree day sums. We also made use of slope stability modeling to test what factors controlled the stability of the area. Models indicate that even a small increase in the water table reduces the factor of safety to < 1, leading to failure. We posit that a combination of permafrost thaw from increasing average temperatures, progressive weakening of the basal shear zone from several years of movement, and an increase in pore-fluid pressure from snowmelt led to the 28 June collapse. Material volumes were estimated using structure from motion (SfM) models incorporating photographs from two field expeditions on 8 July 2022 – 10 d after the slide. Detailed mapping and SfM models indicate that ∼ 1 258 000 ± 150 000 m3 of material was deposited at the slide toe and ∼ 1 340 000 ± 133 000 m3 of material was evacuated from the source area. The Chaos Canyon landslide may be representative of future dynamic alpine topography, wherein slope failures become more common in a warming climate.
| Original language | English |
|---|---|
| Pages (from-to) | 1251-1274 |
| Number of pages | 24 |
| Journal | Earth Surface Dynamics |
| Volume | 11 |
| Issue number | 6 |
| Early online date | 8 Dec 2023 |
| DOIs | |
| Publication status | Published - Dec 2023 |
Bibliographical note
Funding Information:This research has been supported by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (grant no. 80NM0018D0004). We also received support from the French ANR-PIA funding program (grant no. ANR-18-MPGA-0006).
Funding Information:
The first author would like to thank Harrison Gray (USGS) for sending the initial video of this landslide posted to Twitter that spurred this research to action. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). We would also like to acknowledge the support of the French ANR-PIA funding program (ANR-18-MPGA-0006). We thank the developers of the digital image correlation code we implemented with Google Earth imagery: https://github.com/bickelmps/DIC_FFT_ETHZ (last access: 26 January 2023). We also thank Tim Weinmann and Jill Baron for their time for early fieldwork and fruitful conversations in the drafting of this paper. Thank you also to David O'Leary of the USGS Utah Water Science Center for his confidence and Katherine Dahm for early support on this project. We would also like to thank Sean Lahusen, Alex Tye, and an anonymous reviewer for the time and energy to make this a better paper.
Publisher Copyright:
© Author(s) 2023.
Funding
This research has been supported by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (grant no. 80NM0018D0004). We also received support from the French ANR-PIA funding program (grant no. ANR-18-MPGA-0006). The first author would like to thank Harrison Gray (USGS) for sending the initial video of this landslide posted to Twitter that spurred this research to action. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). We would also like to acknowledge the support of the French ANR-PIA funding program (ANR-18-MPGA-0006). We thank the developers of the digital image correlation code we implemented with Google Earth imagery: https://github.com/bickelmps/DIC_FFT_ETHZ (last access: 26 January 2023). We also thank Tim Weinmann and Jill Baron for their time for early fieldwork and fruitful conversations in the drafting of this paper. Thank you also to David O'Leary of the USGS Utah Water Science Center for his confidence and Katherine Dahm for early support on this project. We would also like to thank Sean Lahusen, Alex Tye, and an anonymous reviewer for the time and energy to make this a better paper.
| Funders | Funder number |
|---|---|
| ANR-PIA | ANR-18-MPGA-0006 |
| National Aeronautics and Space Administration | 80NM0018D0004 |
| National Aeronautics and Space Administration | |
| Jet Propulsion Laboratory | |
| California Institute of Technology |