Faculté des géosciences et de l'environnement Institut ?· Faculté des géosciences et de l'environnement…

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  • Facult des gosciences 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

    )

    0

    10

    20

    30

    40

    50

    60

    Distance (m)

    30.07.200913 iterationsDeviation RMS : 3.02 %

    F03/09

    0 20 30 40 50 7060 9080 10010

    0

    32

    64

    96 m

    2660

    2650

    2640

    2630

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    2610

    2600

    2590

    2580

    Alti

    tude

    (m)

    B3

    06.07.20095 iterationsError RMS : 1.67%

    Electrical resistivity (km)

    2 10 20 50 100 200

    1 5 15 30 75 150 500

    4500

    3500

    2000

    1000

    3000

    1500

    4000

    2500

    500

    5000

    VP (m/s)

    F02/09

    B2

    B1A

    B

    C

    A

    B

    C

    D

    D

    B3

    B2

    B1Frozen body

    0

    5

    10

    15

    20

    25

    -4 -2 0 2 4

    Dep

    th (m

    )

    Temperature (C)

    0

    5

    10

    15

    20

    25

    -4 -2 0 2 4

    Dep

    th (m

    )

    Temperature (C)

    < -12

    -12 to -8

    -8 to -6

    -6 to -4

    -4 to -3

    -3 to -LCD

    -LDC to +LDC

    +LDC to 3

    3 to 4

    4 to 6

    6 to 8

    > 12

    AbsoluteChange [m]

    0 5 10

    km

    Franz Josef Glacier

    Tasman Glacier

    Fox Glacier

    0

    10

    50

    70

    16-d displacement (m

    )

    0

    5

    Velo

    city

    (m d

    -1)

    GCM: Our primary objective is to establish a mechanistic and quantitative understanding of the processes that govern the form and evolution of the Earths 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

    Gomorphologie, Cryosphre 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

    Lum

    ines

    cenc

    e si

    gnal

    Depth (mm)

    Glacier de Ferpcle

    Calibration for OSL-exposure dating

    0 0.2 0.4 0.6 0.8 10

    0.2

    0.4

    0.6

    0.8

    1

    Predicted n/N (Kars et al. 2008)

    Mea

    sure

    d n/

    N

    50 10 2015

    Fading rate (%/decade)

    Thermal signature

    Forbidden zone

    field s

    teady-

    state

    LIDAR scan of a proglacial river

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