Large landslides cluster at the margin of a deglaciated mountain belt

• Published in: Scientific Reports
• Main Authors: Tomáš Pánek, Michal Břežný, Stephan Harrison, Elisabeth Schönfeldt, Diego Winocur
• Format: Article in Journal/Newspaper
• Language: English
• Published: Nature Portfolio 2022
• Subjects: Medicine; R; Science; Q; Patagonia; Ice Sheet
• Online Access: https://doi.org/10.1038/s41598-022-09357-9; https://doaj.org/article/4feb1b9c65a949079a07a9f5cc338ec3

Abstract Landslides in deglaciated and deglaciating mountains represent a major hazard, but their distribution at the spatial scale of entire mountain belts has rarely been studied. Traditional models of landslide distribution assume that landslides are concentrated in the steepest, wettest, and most tectonically active parts of the orogens, where glaciers reached their greatest thickness. However, based on mapping large landslides (> 0.9 km2) over an unprecedentedly large area of Southern Patagonia (~ 305,000 km2), we show that the distribution of landslides can have the opposite trend. We show that the largest landslides within the limits of the former Patagonian Ice Sheet (PIS) cluster along its eastern margins occupying lower, tectonically less active, and arid part of the Patagonian Andes. In contrast to the heavily glaciated, highest elevations of the mountain range, the peripheral regions have been glaciated only episodically, leaving a larger volume of unstable sedimentary and volcanic rocks that are subject to ongoing slope instability.