Geophysics - Research

We investigate climate-relevant Earth system problems including the stability of ice sheets and processes in the critical zone. Our tools include airborne and ground-based georadar, satellite- and ground-based radar interferometry, LiDAR, GNSS, and numerical modeling.  If you are interested to join this group on a BSc, MSc, Ph.D. or postdoctoral level, do not hesitate to contact us. We have succesfull experience in writing grant proposals, also within the German scholarschip scheme. We believe that we are helpful, supportive and friendly people.

 

Research Projects (MSc, BSc)

Projects in Summer 2021

In Summer 2021 a group of students has formed for research in the Lauswiesen. There we try to close the water budget for this well instrumented test site. How much of the rain is taken up by ground-water, how much by evapotranspiration and how much is lost by direct run-off? We investigate this with a number of tools such as ground-penetrating radars, seismics,  automatic weather stations and soil moisture sensors. On a good day we hope that all of these tools will eventually tell us a coherent story. If you want to join the Lauswiesen Project contact us or Dr. C. Leven.

Projects in Summer 2020

In 2020 we complemented research of the CAMPOS project with a seismic refraction survey (cf MSc M. Erb). The goal was to image through the critical zone and find at which depth we could identify the bedrock in the hillslopes.

Research Methods

Ground-Penetrating Radar

Ground-Penetrating Radar uses electromagnetic waves for subsurface imaging across a number of disciplines. In Glaciology it is the number one tool for measuring ice thickness and internal stratigraphy. It is also used to derive key parameters such as ice temperature, ice anisotropy, basal properties (e.g. wet vs dry bed) or crevassing.

Terrestrial Radar Interferometry

Terrestrial Radar Interferometry is a comparatively novel technique using a coherent imaging radar system which scanns surfaces at high temporal and spatial resolution. Interferometric differencing of subsequent aquisitions enables interferometric change detection within the mm range. We use this instrument to detect temporal variations glacier flow. Other applications include geohazard applications, for example in mining, landslide detection/prediction or rockfall. 

Data Analysis and Numerical Modelling

Data analysis and signal processing is at the core of many of our projects. Methods applied include classical time series analysis (e.g., fourier analysis, filtering), statistical methods (e.g., principal component analysis) and various invesion schemes.

We use numerical and analytical models to interpret field data and to better understand ice-sheet dynamics. Tools we use are the finite element, full Stokes model Elmer/Ice together with various radar forward models (raytracing, exploding reflectors, matrix based models,..).

Rover Development

Automated rovers are ideally suited to carry geophysical instruments in hazardous areas (e.g., some parts of Antarctic) or to carry out measurements requiring repetitive sampling of profiles (e.g., inflitration experiments or groundwater monitoring). In collaboration with industry and university partners (here Polar Research Equipment) we aim to implement automated rovers as a standard tool for some geophysical monitoring techniques.

Seismiks

Refraction seismics is an ideal tool for shallow sub-surface imaging, e.g., for detecting the depth to bedrock, the extent of the weathering front or identification of aquifer characteristics. On ice, seismics are use to characterice the ice-bed interface (e.g., soft vs. hard bed) or internal ice propeties such as the bulk ice crystal orientation.

LiDAR

Lidar is a tool for measuring 3D point clouds using a high-performance laser beam. We use the instrument in collaboration within the Earth System Dynamics Group (Prof. Ehlers) for change detection (e.g. rock fall) and characterization of exposed fault surfaces. Lidar has extensive applications in other industries such as autonomous driving, robotics, or anywhere else where 3D models are required.