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Research

Below you find an overview of our current research. Click the links to find out more about each topic! You can have a closer look at all the images & figures by clicking on them.

Biogeochemical processes in the oceanic lithosphere

Ophicalcite from the Northern Appenine ophiolite, Italy

Hydrothermal alteration of ultramafic rocks has a major impact on the global biogeochemical cycles. In our group we study the links between mineral reactions and biogenic activity and how these chemical interactions impact global geochemical cycles.

Fluid flow in subduction zones and orogens

Spontaneous development of porosity fingers during dehydration. Dehydration starts from the top of the simulation and proceed downwards.

Fluids play a crucial role in subduction zone processes and during continental collisions. As such, subduction zones are the key location linking Earth’s surficial and internal geochemical reservoirs. During metamorphic dehydration reactions fluids escape from the downgoing slab into the overlying mantle wedge affecting the rheology of the slab-mantle interface and controlling many geochemical cycles, magmatic processes, and earthquakes.

Thermodynamics of fluids and rocks

P/T Phase diagram of a hydrated peridotite, calculated with THERMOLAB

Understanding the thermodynamic behavior of fluids and rocks is crucial to correctly interpret mineralogical and petrological observations in the field. Thermodynamics is used in chemical equilibrium calculations for phase diagrams, as well as in numerical modelling of non-equilibrium processes such as reactive fluid flow and rock deformation. As fluids facilitate reactions in rocks which in turn affect transiently its flow -sensitive porosity, it is of main importance to properly characterize the thermodynamic behavior of geological fluids. We focus on quantification of the composition of fluids and minerals using theory, experiment, and observation.

Fluids and volatiles in the solar system

BSE image of a meteorite, created on our SEM

Different planetary materials show variable degrees of volatile element depletions, the origin and timing of which are still debated. We investigate carbonaceous chondrites, the components of the remnant material of planetary formation, and use stable isotope signatures of volatile metals to understand the origin of these depletions. 

Time scales of metamorphic and metasomatic processes

Osczillatory zonation of Mn in a garnet grain from the Tianshan high-pressure metamorphic belt in China.

Exhumed rocks provide insight into global geodynamic and plate tectonic processes. Using a combination of detailed petrology, isotope geochemistry and thermodynamic modelling allows us to provide constraints on rates and timescales of subduction, exhumation, hydration or dehydration processes during orogenesis.

Fluids and geophysics: influence of mineral reactions on petrophysical properties

FEM model of real mapped structures by Sascha Zertani

Examining how mineral reactions change rheological and petrophysical rock properties is crucial to understand the dynamics of the solid Earth. Using field mapping of exhumed deformed rocks, detailed analysis of the rock-forming mineral assemblages on various scales, experiments involving reaction and deformation, and numerical simulations we develop the understanding of processes such as subduction, mountain building, and earthquakes.