Research

Benning Lab Research Page

Group

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experimental projects

My research area is linked to the quantitative elucidation of geochemical reaction mechanisms and pathways at low to hydrothermal temperatures in inorganic and biologic systems. My group focuses on problems related to the speciation, transport, release, and sequestration of a series of elements in Earth surface environments as well as on processes linked to metal and nutrient cycling in mixed mineral-microbial systems.

More information can be found in the group or publication and group pages via the links at top.

We are applying a variety of experimental (and some field) approaches to study the making and breaking of mineral bonds and to elucidate crucial thermodynamic and kinetic parameters in various mineral systems. In addition we are evaluating several mineral-microbial interaction processes.

We study processes linked to:
(a) the nucleation, growth and crystallization of mineral phases in the absence or presence or additives (e.g., silica, iron oxides, carbonates, sulfides/sulfates)
(b) the abiotic and biotic dissolution of rocks and minerals (e.g., shales, biotite, pyrite)
(c) biomineralization (e.g., thermophillic/cryogenic, magnetotactics, organic templates)
(d) weathering (biotite, shales)

Experimental techniques regularly applied include mineral synthesis at low temperature to hydrothermal temperatures using various autoclaves and reactors and their characterization using various conventional and high-resolution X-ray diffraction, light and X-ray scattering as well as spectroscopic approaches.

We also apply various geobiological approaches from culturing to metagenomics in order to elucidate community diversity and function in mixed mineral-biofilm systems, or to quantify stress adaptations to changes in physico-chemical environments (i.e., metal concentrations, T, pH, UV etc), in both experimental and natural field settings.

A large part of my groups work is focused on the use of synchrotron-based techniques to elucidate molecular level reaction mechanisms via the development and application of in situ and realtime techniques to quantify reactions as they occur (e.g., small of wide angle X-ray scattering, hard and soft-X-ray absorption spectroscopy) or use mapping and quantification of functional group distributions (µ-Fourier Transform Infrared or Scanning Transmission X-ray Microscopy) to elucidate various microbial biochemical signals.

Field-work in the last few years mostly focus on extreme environments either in geothermal settings like Iceland or New Zealand or in cryogenic environments (cold deserts) in the Arctic (Svalbard, Iceland and Greenland).