Large-volume rock slope failures are one of the main hazards in high mountain glaciated valleys, inducing severe damage to population and infrastructure, representing a high risk for society, ecosystems and infrastructure. The Andes Mountain Range is shaped by glacial activity and therefore by megalandslides due to changes in shear strength and deformation during periods of glaciation and deglaciation, which modify the slope stress state and, along with other processes, induce progressive damage in the rock mass, eventually leading to failure. The study focuses on validating the hypothesis that glacier unloading contributes to these types of landslides. The research numerically modelled the effects of glacier unloading on stress distribution and its potential impact on landslides, particularly using two Chilean cases: The 1987 Estero Parraguirre and the 2018 Yerba Loca rock slides. These models used the Universal Distinct Element Code, along with geological and geotechnical data from previous studies and field observations. The numerical results showed that the combination of shear stress changes due to glacial unloading and structural control from main discontinuities could cause landslides, with the deglaciation of glaciers potentially preparing the slope for catastrophic failure that may occur due to external climatic or tectonic triggers. The results suggest that stress redistribution and damage to the rock mass caused by deglaciation can lead to progressive failure. Further work is needed to understand better the slope failure mechanics to assess the geohazards in the Andes and other mountain regions.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Price excludes VAT (USA)
Tax calculation will be finalised during checkout.
Allen S, Cox S, Owens I (2011) Rock avalanches and other landslides in the central Southern Alps of New Zealand: a regional study considering possible climate change impacts. Landslides 8:33–48
Antinao JL, Gosse J (2009) Large rockslides in the Southern Central Andes of Chile (32–34.5°S): tectonic control and significance for quaternary landscape evolution. Geomorphology 104:117–133
Bruckner T, Farías-Barahona D, Fürst JJ, Mergili M, Sepulveda S, Peña H, Casassa G, Braun M (2021) Reconstruction constraints on the Estero Parraguirre ice-rock avalanche in 1987, Central Andes of Chile: new insights from remote sensing and numerical modeling. In: European geosciences union annual conference, p EGU21–13019
Burgos K (2022) Study of the 16.12.2017 slope failure in Villa Santa Lucia. Dissertation, Universidad de Chile (in Spanish)
Carrasco J, Sepúlveda SA, Lara M, Rosales V (2023) Evidencias de expansión del deslizamiento activo de Yerba Loca, Andes centrales. Rev Asoc Geol Argent 80(2) (in Press)
Casassa G, Marangunic C (1993) The 1987 Rio Colorado Rockslide and Debris Flow, Central Andes, Chile. Environ Eng Geosci 3:321–330
Charrier R, Iturrizaga L, Carretier S, Regard V (2019) Geomorphologic and glacial evolution of the Cachapoal and Southern Maipo catchments in the Andean Principal Cordillera, Central Chile (34°–35°S). Andean Geol 46:240–278
Cossart E, Braucher R, Fort M, Bourlès DL, Carcaillet J (2008) Slope instability in relation to glacial debuttressing in alpine areas (upper Durance Catchment, Southeastern France): evidence from field data and 10Be cosmic ray exposure ages. Geomorphology 95:3–26
Costa JE, Schuster RL (1988) The formation and failure of natural dams. Geol Soc Am Bull 100:1054–1068
Deckart K, Pinochet K, Sepúlveda SA, Pinto L, Moreiras SM (2014) New insights on the origin of the Mesón Alto deposit, Yeso Valley, central Chile: a composite deposit of glacial and landslide processes? Andean Geol 41:248–258
DGA (2022) Inventario Público de Glaciares, actualización 2022. Ministerio de Obras Públicas, Dirección General de Aguas. https://dga.mop.gob.cl/Paginas/InventarioGlaciares.aspx
Duhart P, Sepúlveda V, Garrido N, Mella M, Quiroz D, Fernández J, Moreno H, Hermosilla G (2019) The Santa Lucia landslide disaster, Chitén-Chile: origin and effects. In: Proceedings of the 7th international conference on debris-flow hazards mitigation, Golden, Colorado
Eisenberg A, Pardo M (1988) Report on seismic activity related to debris flow, Estero Parraguirre, Central Chile. Sci Alert Netw Bull 13:15–16
Fan X, Xu Q, Alonso-Rodriguez A, Subramanian SS, Li W, Zheng G, Dong X, Huang R (2019) Successive landsliding and damming of the Jinsha River in eastern Tibet, China: prime investigation, early warning, and emergency response. Landslides 16:1003–1020
Geertsema M, Menounos B, Bullard G, Carrivick JL, Clague JJ, Dai C et al (2022) The 28 november 2020 landslide, tsunami, and outburst flood – A hazard cascade associated with rapid deglaciation at Elliot Creek, British Columbia Canada. Geophys Res Lett 49:e2021GL096716. https://doi.org/10.1029/2021GL096716
Grämiger LM, Moore JR, Gischig VS, Ivy-Ochs S, Loew S (2017) Beyond debuttressing: mechanics of paraglacial rock slope damage during repeat glacial cycles. J Geophys Res Earth Surf 122(4):1004–1036. https://doi.org/10.1002/2016JF003967
Grämiger LM, Moore JR, Gischig VS, Loew S, Funk M, Limpach P (2020) Hydromechanical rock slope damage during Late Pleistocene and Holocene glacial cycles in an alpine valley. J Geophys Res Earth Surf. https://doi.org/10.1029/2019JF005494
Gruber S (2012) Derivation and analysis of a high-resolution estimate of global permafrost zonation. Cryosphere 6:221–233
Guthrie RH, Friele P, Allstadt K, Roberts N, Evans SG, Delaney KB, Roche D, Clague JJ, Jakob M (2012) The august 6th 2010 Mount Meager rock slide-debris flow, Coast Mountains, British Columbia: characteristics, dynamics, and implications for hazard and risk assessment. Nat Hazards Earth Syst Sci 12:1277–1294
Hauser A (2002) Rock avalanche and resulting debris flow in Estero Parraquirre and Río Colorado, Región Metropolitana, Chile. Geol Soc Am Rev Eng Geol XV:135–148
Itasca (2019) Universal distinct element code, version 7.0 user’s manual. Itasca Consulting Group Inc., Minneapolis, Minnesota
Lliboutry L (2002) Extension of Glacier de Saint-Sorlin, French Alps, and equilibrium-line altitude during the little ice age. J Glaciol 48:118–124. https://doi.org/10.3189/172756502781831548
Marangunic C (1979) Inventario de Glaciares Hoya del Río Maipo Santiago. Ministerio de Obras Publicas Dirección General de Aguas, Santiago, Chile
McColl ST (2012) Paraglacial rock-slope stability. Geomorphology 153–154:1–16
Moreiras SM, Sepúlveda SA (2015) Megalandslides in the Andes of Central Chile and Argentina (32°–34°s) and potential hazards. In: Sepúlveda SA et al (eds) Geodynamic processes in the Andes of Central Chile and Argentina. Geological Society of London, London, pp 329–344
Palma (2022) Tridimensional modelling of the Villa Santa Lucia 2017 megalandslide due to progressive failure. In: MSc Thesis in civil engineering, Universidad de Chile (in Spanish)
Pellitero R, Rea BR, Spagnolo M, Bakke J, Ivy-Ochs S, Frew CR, Renssen H (2016) GlaRe, a GIS tool to reconstruct the 3D surface of palaeoglaciers. Comput Geosci 94:77–78
Rivillo V (2018). Slope stability analysis of Cerro Rabicano (Cajón del Maipo) affected by a rock slide using numerical modelling. Dissertation, Universidad de Chile (in Spanish)
Rosales V. (2022) 2D numerical modelling of slope stability in paraglacial environments: the case of Yerba Loca landslide, Santiago, Region Metropolitana. Dissertation, Universidad de Chile (in Spanish)
Sepúlveda SA, Alfaro A, Lara M, Carrasco J, Olea-Encina P, Rebolledo S, Garcés M (2021) An active large rock slide in the Andean paraglacial environment: the Yerba Loca landslide, central Chile. Landslides 18:697–705
Sepúlveda SA, Moreiras SM, Chacón D, Villaseñor T, Jeanneret P, Poblete F (2022) The Pangal landslide complex, Cachapoal basin, central Chile (34°S): an example of a multi-temporal slope instability cluster in the Andes. J S Am Earth Sci 115:103769
Sernageomin - Servicio Nacional de Geología y Minería (2019) Remoción en masa en Santuario de la Naturaleza Yerba Loca. Servicio Nacional de Geología y Minería, INF-2019. METROPOLITANA-01, Santiago
Thiele R (1980) Hoja Santiago. Región Metropolitana. Carta Geológica de Chile, escala 1: 250.000. Instituto de Investigaciones Geologicas, Santiago
Tobar C (2021) 2D slope stability numerical modelling in paraglacial environments: the case of Parraguirre landslides, San Jose de Maipo. Dissertation, Universidad de Chile (in Spanish)
Valenzuela L, Varela J (1991) El Alfalfal rock fall and debris flow in Chilean Andes Mountains. In: Proceedings, panamerican conference on soil mechanics and foundation engineering, Viña del Mar, Chile, p 357-371
This work was funded by ANID Fondecyt 1201360 grant (S.S., F.O., M.L.) and Simon Fraser University Faculty Recruitment Grant (S.S.). In addition, the authors thank Shantal Palma and Patricio Gómez (Itasca Chile) for their support in modelling, Sofía Rebolledo, Javiera Carrasco, and Karla Burgos for their collaboration in the fieldwork, and Felipe Ugalde and Alejandro Alfaro for their fruitful discussions on the subject.
This work was funded by ANID Fondecyt 1201360 grant (S.S., F.O., M.L.) and Simon Fraser University Faculty Recruitment Grant (S.S.).
The authors have no relevant financial or non-financial interests to disclose.
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
About this article
Cite this article
Sepúlveda, S.A., Tobar, C., Rosales, V. et al. Megalandslides and deglaciation: modelling of two case studies in the Central Andes. Nat Hazards 118, 1561–1572 (2023). https://doi.org/10.1007/s11069-023-06067-x