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Page 1: Faculté des géosciences et de l'environnement Institut … · Faculté des géosciences et de l'environnement Institut des dynamiques de la surface terrestre We have adopted a multi-disciplinary

Faculté des géosciences et de l'environnementInstitut des dynamiques de la surface terrestre

We have adopted a multi-disciplinary approach that includes four main compo-nents. First is the construction of numerical models based on physical laws that describes fluvial, glacial and periglacial processes.

Second is field experimentation. We conduct fieldwork, primarily in mountainous terrain. Our objective is to collect data to better understand the geomorphic res-ponses of fluvial, glacial and periglacial processes to changes in climate, unravel interactions between tectonics, erosion and climate, manage risks associated with rivers, glaciers and hillslopes processes and, finally, understand the linkages between ecological and geomorphological processes.

Third is experimental work for low-temperature thermochronology, luminescence dating and cosmogenic nuclide dating.

Fourth, we use remote sensing methods (image analysis, photogrammetry, laser scanning, InSAR) to quantify recent landscape response to climate and human forcing but also to provide critical information for initializing and validating physical models.

Permafrost investigations in the Petit Mont Rouge talus slope (Arolla):- location of the boreholes- borehole stratigraphies and thermal pro-files- electrical resistivity tomography profile- seismic refraction tomography profile - limits of the frozen body.The arrows show the air movement in winter, evidenced by thermal data.

Dep

th (m

)

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Distance (m)

30.07.200913 iterationsDeviation RMS : 3.02 %

F03/09

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tude

(m)

B3

06.07.20095 iterationsError RMS : 1.67%

Electrical resistivity (kΩm)

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1 5 15 30 75 150 500

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VP (m/s)

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< -12

-12 to -8

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-3 to -LCD

-LDC to +LDC

+LDC to 3

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Franz Josef Glacier

Tasman Glacier

Fox Glacier

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city

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GCM: Our primary objective is to establish a mechanistic and quantitative understanding of the processes that govern the form and evolution of the Earth’s surface. These processes include (1) geomorphic processes that convert bedrock to sediment, (2) climatic and ecological processes that control geomorphic processes and which in turn respond to them, (3) the fluxes of ice, water and (ice-cemented) sediment that follow, (4) the reaction of the cryosphere to the climate change and (5) tectonic processes that deform rocks and expose it at the surface.

Geomorphology, Cryosphere and Mountains

Géomorphologie, Cryosphère et Montagnes

Movements measured with RTK GPS on the Rognes and Pierre Ronde proglacial areas between 2011 and 2012 (Mont Blanc Massif - France).

Tectonics, precipitation and low thermochronology in the St Elias Range of Alaska

Exhumation history in the Patagonian Andes, inverted from low temperature thermochronometric data

Exhumation history in the St Elias Range of Alaska

Glacier displacements in the Southern Alps of New Zealand

Rock glaciers 3D-displacements in val d'Herens, Swizterland

Global erosion rates from low thermochronometric data(color scheme is erosion rates from 0.01 mm/yr in blue to 7 mm/yr in red)

Glacial erosion model in the Alps for 100 kyr

The management of risks associated with river and hillslope processes, including flood risk,

and innovative and non-standard approaches to risk management

The interface between flow hydraulics, geomorphology and aspects of in-stream ecology; modelling over a range of scales.

ASTER image of the Bering Glacier in southern Alaska

Loess sampling for OSL datingUnderstanding the kinetics of OSL dating

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cenc

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gnal

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Glacier de Ferpècle

Calibration for OSL-exposure dating

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sure

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50 10 2015

Fading rate (%/decade)

Thermal signature

Forbidden zone

field steady-s

tate

LIDAR scan of a proglacial river

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