Postglacial Patagonian mass movement: From rotational slides and spreads to earthflows

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61988987%3A17310%2F20%3AA21028JJ" target="_blank" >RIV/61988987:17310/20:A21028JJ - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0169555X20302890" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0169555X20302890</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.geomorph.2020.107316" target="_blank" >10.1016/j.geomorph.2020.107316</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Postglacial Patagonian mass movement: From rotational slides and spreads to earthflows

Popis výsledku v původním jazyce

Many of the volcanic plateau margins of the eastern, formerly glaciated, foreland of the Patagonian Andes are undermined by giant landslides (≥108 m3). One cluster of such landslides extends along the margin of the Meseta del Lago Buenos Aires (MLBA) plateau that is formed mainly by Neogene-Quaternary basalts. The dry climate is at odds with numerous >2-km long earthflows nested within older and larger compound landslides. We present a hydrological analysis, a detailed geomorphic map, interpretations of exposed landslide interiors, and radiocarbon dating of the El Mirador landslide, which is one of the largest and morphologically most representative landslide. We find that the presence of lakes on top of the plateau, causing low infiltration rates, correlates negatively with the abundance of earthflows on compound landslides along the plateau margins. Field outcrops show that the pattern of compound landslides and earthflows is likely controlled by groundwater seepage at the contact between the basalts and underlying soft Miocene molasse. Numerous peat bogs store water and sediment and are more abundant in earthflow-affected areas than in their contributing catchment areas. Radiocarbon dates indicate that these earthflows displaced metre-thick layers of peat in the late Holocene (<2.5 ka). We conclude that earthflows of the MLBA plateau might be promising proxies of past hydroclimatic conditions in the Patagonian foreland, if strong earthquakes or gradual crustal stress changes due to glacioisostatic rebound can be ruled out.

Název v anglickém jazyce

Postglacial Patagonian mass movement: From rotational slides and spreads to earthflows

Popis výsledku anglicky

Many of the volcanic plateau margins of the eastern, formerly glaciated, foreland of the Patagonian Andes are undermined by giant landslides (≥108 m3). One cluster of such landslides extends along the margin of the Meseta del Lago Buenos Aires (MLBA) plateau that is formed mainly by Neogene-Quaternary basalts. The dry climate is at odds with numerous >2-km long earthflows nested within older and larger compound landslides. We present a hydrological analysis, a detailed geomorphic map, interpretations of exposed landslide interiors, and radiocarbon dating of the El Mirador landslide, which is one of the largest and morphologically most representative landslide. We find that the presence of lakes on top of the plateau, causing low infiltration rates, correlates negatively with the abundance of earthflows on compound landslides along the plateau margins. Field outcrops show that the pattern of compound landslides and earthflows is likely controlled by groundwater seepage at the contact between the basalts and underlying soft Miocene molasse. Numerous peat bogs store water and sediment and are more abundant in earthflow-affected areas than in their contributing catchment areas. Radiocarbon dates indicate that these earthflows displaced metre-thick layers of peat in the late Holocene (<2.5 ka). We conclude that earthflows of the MLBA plateau might be promising proxies of past hydroclimatic conditions in the Patagonian foreland, if strong earthquakes or gradual crustal stress changes due to glacioisostatic rebound can be ruled out.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10508 - Physical geography

Projekt

<a href="/cs/project/GA19-16013S" target="_blank" >GA19-16013S: Obří sesuvy na předpolí ledovců: chybějící část příběhu vývoje Patagonského ledovcového štítu a přilehlých ledovcových jezer</a><br>

Návaznosti

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

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

GEOMORPHOLOGY

ISSN

0169-555X

e-ISSN

—

Svazek periodika

367

Číslo periodika v rámci svazku

October

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

16

Strana od-do

107316

Kód UT WoS článku

000564546600001

EID výsledku v databázi Scopus

2-s2.0-85087343377