Medal for Research Excellence 2009

Max Wilke

Max Wilke is an impressive Earth scientist who has successfully worked on a number of areas, from experimental geochemistry to field-based petrological problems. He has a very broad knowledge in the field of geology, mineralogy, fluid- and melt-rock interaction, and has published significant contributions to rather diverse topics such as material science, biomaterials, silicate-melt properties, heat and mass transport in contact aureoles, and others. This shows one of his many strengths: he has not only excellent expertise in a large number of geochemical and mineralogical methods, but also knows how to efficiently combine them in order to obtain a maximum insight into a scientific question.

In that, he is interdisciplinary indeed. His recent publications show him at the forefront of experimental geochemistry. The hallmark of Max WILKE’s contributions to Mineral Sciences is the application of in-situ spectroscopic techniques to investigate properties of Earth materials under high pressure and temperature. He developed highly improved experimental setups and analytical procedures at the ERSF (Grenoble, France) and DESY (Hamburg, Germany) synchrotron radiation facilities and applied X-ray absortion spectroscopy (EXAFS, XANES) to a number of problems. Important studies include the determination of the oxidation state of iron in minerals, the speciation and structural environment of iron and sulphur in silicate glasses and melts, and the dependence of speciation on water fugacities. One of the many important results is that cooling has a major effect on the local environment of cations in melts, and that information obtained from quenched melts is ambiguous. Max WILKE’s papers perfectly highlight the importance of experimental in-situ studies for understanding melt structures. These results are of paramount importance for the interpretation of magmatic processes in general. Using his vast expertise on synchrotron-based microanalytical methods, Max WILKE has significantly contributed to the determination of mineral solubilites in water and hydrous melts by in-situ synchrotron radiation micro-X-ray fluorescence. Here, dissolution and dissolution kinetics are measured by XRF in hydrothermal diamond anvil cells. The method determines dissolution kinetics up to saturation. Most importantly, the work has shown that the validity of conventional solubility studies at high pressures and temperatures may be hampered by incomplete equilibrium between solids and fluid. It is clear that such data are essential for the interpretation of mass transport by fluids in the Earth’s crust.

Recently, Max WILKE has started to apply resonant inelastic X-ray scattering (RIXS) to the determination of electronic states in solid Earth materials. This highlights his ability and willingness to explore new experimental and analytical pathways and adapt them for Geomaterials’ Science. In that, he is a truly innovative scientist.

EMU’s annually awarded Silver Medal for Research Excellence is for young scientists who make not only significant contributions to research, but who are also active in strengthening European scientific links. Max WILKE is exemplary also with respect to the latter. Max WILKE’s expertise is recognized internationally. He is invited to give several key-note talks and he is organizing sessions at several meetings. He is member of committees for the attribution of working time at the Synchrotron facility (ESRF). He is author and co-author of more than 30 peer-reviewed publications in first class journals. The topics of the publications show the diversity of the research areas of Max WILKE, going from material science, investigations of biomaterials, experimental geochemistry to field work and petrology. Several publications show his ability to conduct highly interdisciplinary studies with complementary methods. His recent activities at the University of Potsdam also showed his broad knowledge of methods in Earth sciences: he was responsible for the teaching in crystallography and for optical microscopy, he was supervising field work and organising excursions on metamorphic and magmatic topics.