Controls on spatial and temporal patterns of slope deformation in an Alpine valley

Autor: Philippe Limpach, L. Longuevergne, Marc Hugentobler, Clément Roques, Jordan Aaron, Simon Loew, Nicolas Oestreicher, Adriano Gualandi
Přispěvatelé: Department of Earth Sciences [Swiss Federal Institute of Technology - ETH Zürich] (D-ERDW), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Université de Neuchâtel (UNINE), Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Roma (INGV), Istituto Nazionale di Geofisica e Vulcanologia, Géosciences Rennes (GR), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Department of Civil, Environmental and Geomatic Engineering [ETH Zürich] (D-BAUG), Swiss National Science Foundation (project 172492), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Federal Office for the Environment (FOEN)
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Journal of Geophysical Research: Earth Surface
Journal of Geophysical Research: Earth Surface, American Geophysical Union/Wiley, In press, ⟨10.1029/2021jf006353⟩
Journal of Geophysical Research: Earth Surface, 2021, 126 (12), pp.e2021JF006353. ⟨10.1029/2021jf006353⟩
Journal of Geophysical Research: Earth Surface, 126 (12)
ISSN: 0148-0227
2169-9003
2169-9011
DOI: 10.1029/2021jf006353⟩
Popis: A comprehensive surface displacement monitoring system installed in the recently deglaciated bedrock slopes of the Aletsch Valley shows systematic reversible motions at the annual scale. We explore potential drivers for this deformation signal and demonstrate that the main driver is pore pressure changes of groundwater in fractured granitic mountain slopes. The spatial pattern of these reversible annual deformations shows similar magnitudes and orientations for adjacent monitoring points, leading to the hypothesis that the annually reversible deformation is caused by slope-scale groundwater elevation changes and rock mass properties. Conversely, we show that the ground reaction to infiltration from snowmelt and summer rainstorms can be highly heterogeneous at local scale, and that brittle-ductile fault zones are key features for the groundwater pressure-related rock mass deformations. We also observe irreversible long-term trends (over the 6.5 yr dataset) of deformation in the Aletsch valley composed of a larger uplift than observed at our reference GNSS station in the Rhone valley, and horizontal displacements of the slopes towards the valley. These observations can be attributed respectively to the elastic bedrock rebound in response to current glacier mass downwasting of the Great Aletsch Glacier and gravitational slope deformations enabled by cyclic groundwater pressure-related rock mass fatigue in the fractured rock slopes. ISSN:0148-0227 ISSN:2169-9003 ISSN:2169-9011
Databáze: OpenAIRE
Externí odkaz: