The largest rock avalanches in Patagonia: Timing and relation to Patagonian Ice Sheet retreat

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61988987%3A17310%2F23%3AA2402M79" target="_blank" >RIV/61988987:17310/23:A2402M79 - isvavai.cz</a>

Result on the web

<a href="https://pdf.sciencedirectassets.com/271861/1-s2.0-S0277379123X0002X/1-s2.0-S0277379123000100/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEKD%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJHMEUCIH4YYo0s2lXbU92hgPp3Rgp12ARilDwkSV1Fcrln7%2B%2BTAiEAowthJaN" target="_blank" >https://pdf.sciencedirectassets.com/271861/1-s2.0-S0277379123X0002X/1-s2.0-S0277379123000100/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEKD%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJHMEUCIH4YYo0s2lXbU92hgPp3Rgp12ARilDwkSV1Fcrln7%2B%2BTAiEAowthJaN</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.quascirev.2023.107962" target="_blank" >10.1016/j.quascirev.2023.107962</a>

Result language

angličtina

Original language name

The largest rock avalanches in Patagonia: Timing and relation to Patagonian Ice Sheet retreat

Original language description

One of the largest concentrations of giant landslides (≥108 m3) in Patagonia is in the eastern part of Lago Cochrane/Pueyrredón (LP) valley in Argentina. In addition to minor earthflows and rock slides, this landslide cluster is dominated by rock and debris avalanches that affect the northern slope of Meseta Belgrano, the largest of which have volumes >1 km3 and a runout of >10 km. To determine the chronology of these large landslides and their relationship to the geological setting and the glacial history related to the Last Glacial Maximum (LGM) ∼20–18 ka ago, we combined geomorphological mapping with absolute dating (luminescence and radiocarbon dating) and numerical modelling of slope stability. Dating and cross-cutting relationships with glaciolacustrine deposits suggest that some of the largest rock avalanches collapsed directly into a glacial lake between ∼17 and ∼12 ka, soon after deglaciation, but some were pre-glacial and landslide activity continued until today, posing a potential hazard to the area. In agreement with these data, numerical modelling suggests that slope stability was only marginally affected by ice retreat and glacial lake drainage, and landslides were most likely favoured by relatively low rock strength, related glacially-conditioned topography, and, possibly, seismic activity. A newly identified active fault at the base of the Meseta Belgrano, whose activity was likely enhanced by postglacial rebound, was probably the key factor that concentrated postglacial rock avalanches into the LP valley. We conclude that exceptionally large (km-scale) landslides can occur on slopes made of relatively weak rocks in a glacially-conditioned topographic setting even without a strong direct triggering effect of deglaciation, while fatigue due to long-term seismicity may promote collapse.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10508 - Physical geography

Project

<a href="/en/project/GA19-16013S" target="_blank" >GA19-16013S: Giant landslides in glacier foreland: missing story in the evolution of Patagonian Ice Sheet and related glacial lakes</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Quaternary Science Reviews

ISSN

0277-3791

e-ISSN

—

Volume of the periodical

—

Issue of the periodical within the volume

February

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

18

Pages from-to

1-18

UT code for WoS article

000963236100001

EID of the result in the Scopus database

2-s2.0-85146613176