Ralf Dohmen

Ralf Dohmen

Scientist Dr. rer. nat. 1999, Köln, Germany

Phone: +49 234 32-24394
Room: NA 04/690


Research interests

Experimental and theoretical petrology. My research interest covers various different topics within theoretical and experimental petrology where diffusion or diffusion-controlled processes are involved. It comprises theoretical modeling as well as experiments to understand and quantify the reaction kinetics of multi-phase systems or simply to measure diffusion coefficients for various applications, e.g., mineral rheology or diffusion chronometry.

Some of my current projects are:

  • Pulsed Laser Deposition of silicate thin films and its application to volume and grain boundary diffusion experiments

  • Experimental investigation and modeling of diffusive fractionation of isotopes and elements

  • Thermodynamic modeling of element partitioning between plagioclase and melt

  • Experimental and theoretical studies of diffusion and partitioning behavior of Li in olivine

  • Diffusion modeling of chemical zoning in primitive meteorites to extract cooling rates and identify oxidation events in the solar nebula

  • Modeling of chemical zoning in phenocrysts to determine time scales of magma recharging events

Currently active International Collaborations


Prof J. Blundy (Bristol)
Prof. T. Elliott (Bristol)
Dr. Kate Saunders (Bristol)
Dr. Flurin Vils (Bristol)


Dr. Ralf Milke (FU Berlin)
Dr. Katharina Marquardt (GFZ Potsdam)
Prof. Dominique Lattard (Heidelberg)
Thomas Ludwig (Heidelberg)
Prof. Stefan Weyer (Hannover)
Dr. Timm John (Münster)

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Selected recent publications

  • R. Dohmen, K. Faak, J. Blundy (2017) Chronometry and Speedometry of magmatic processes using chemical diffusion in olivine, plagioclase and pyroxenes

  • Dohmen, R., Ter Heege, J.H., Becker, H.-.W., Chakraborty, S. (2016) Fe-Mg inerdiffusion in orthopyroxene. Amer. Mineral. 101: 2210 – 2221.

  • Schwinger, S., Dohmen, R., Schertl, H.-P. (2016): A combined diffusion and thermal modeling approach to determine peak temperatures of thermal metamorphism experienced by meteorites. Geochimica et Cosmochimica Acta 191, Pages: 255-276

  • Tomascak, Paul, Magna, Tomáš, Dohmen, Ralf (2016): Advances in Lithium Isotope Geochemistry, Springer International Publishing,195 pp, ISBN 978-3-319-01429-6

  • Vogt K, Dohmen R, Chakraborty S (2015): Fe-Mg diffusion in spinel: New experimental data and a point defect based model, Am. Mineral. 100, pages: 2112–2122.

  • Le Guillou C, Dohmen R, Rogalla D, Mueller T, Vollmer C, Becker H-W (2015): New experimental approach to study aqueous alteration of amorphous silicates at low reaction rates. Chem. Geol. 412, pages: 179–192.

  • Jonas L, Mueller T, Dohmen R, Baumgartner L, Putlitz B (2015): Transport-controlled hydrothermal replacement of calcite by Mg-carbonates. Geology 43, pages: 779-782.

  • Lai Y-J, von Strandmann PAEP, Dohmen R, Takazawa E, Elliott T (2015): The influence of melt infiltration on the Li and Mg isotopic composition of the Horoman Peridotite Massif. Geochim. Cosmochim. Acta. 164, pages: 318-332.

  • Magna T, Day JMD, Mezger K, Fehr MA, Dohmen R, Aoudjehane HC, Agee CB (2015): Lithium isotope constraints on crust-mantle interactions and surface processes on Mars. Geochim. Cosmochim. Acta. 162, pages: 46-65.

  • Oeser, M., Dohmen, R., Horn, I. , Schuth, S., Weyer, S. (2015): Processes and time scales of magmatic evolution as revealed by Fe-Mg chemical and isotopic zoning in natural olivines, Geochimica et Cosmochimica Acta, Volume 154, Pages 130-150, DOI: 10.1016/j.gca.2015.01.025

  • von Strandmann, PAEP., Dohmen, R., Marschall, HR., Schumacher, JC., Elliott, T. (2015): Extreme Magnesium Isotope Fractionation at Outcrop Scale Records the Mechanism and Rate at which Reaction Fronts Advance, Journal of Petrology, Volume 56, Issue 1, Pages 33-58, DOI: 10.1093/petrology/egu070

  • Dohmen, R., Blundy, J. (2014): A predictive thermodynamic model for element partitioning between plagioclase and melt as a function of pressure, temperature and composition, American Journal of Science, Volume 314, Issue 9, Pages 1319-1372, DOI: 10.2475/09.2014.04

  • John, T., Gussone, N., Podladchikov, Y.Y., Bebout, G.E., Dohmen R., Halama, R., Klemd, R., Magna, T., Seitz, M. (2012): Volcanic arcs fed by rapid pulsed fluid flow through subducting slabs. Nature Geoscience, doi:10.1038/ngeo1482.

  • Saunders, K., Blundy, J., Dohmen, R., Cashman, K. (2012): Linking petrology and seismology at an active volcano. Science 336, 1023-1027.

  • Saunders, K., Rinnen, S., Blundy, J., Dohmen, R., Klemme, S., Arlinghaus, H.F. (2012): TOF-SIMS and electron microprobe investigations of zoned magmatic orthopyroxenes: First results of trace and minor element analysis with implications for diffusion modeling. Am. Mineral. 97, 532–542.

  • Sano, J., Ganguly, J., Hervig, R., Dohmen, R., Zhang, X.Y. (2011): Neodymium diffusion in orthopyroxene: Experimental studies and applications to geological and planetary problems. Geochim. Cosmochim. Acta. 75, 4684–4698.

  • Marquardt, K., Petrishcheva, E., Abart, R., Gardés, E., Wirth, R., Dohmen, R., Becker, H-W., Heinrich, W. (2010): Volume diffusion of Ytterbium in YAG: thin-film experiments and combined TEM–RBS analysis. Phys. Chem. Mineral. 37, 751-760.

  • Watson, B.E., Dohmen, R. (2010): Non-traditional and Emerging Methods for Characterizing Diffusion in Minerals and Mineral Aggregates. In: Diffusion in Minerals and Melts. Rev. Mineral. Geochem. 72, 61-115.

  • Dohmen, R., Milke, R. (2010): Diffusion in Polycrystalline Materials: Grain Boundaries, Mathematical Models, and Experimental Data. In: Diffusion in Minerals and Melts. Rev. Mineral. Geochem. 72, 921-970.

  • Dohmen, R., Kasemann, S., Coogan, L., Chakraborty, S. (2010): Diffusion of Li in olivine. Part I: Experimental observations and a multi species diffusion model. Geochim. Cosmochim. Acta 74, 274–292.

  • Shimojuku, A., Kubo, T., Ohtani, E., Nakamura, T., Okazaki, R., Dohmen, R., Chakraborty, S. (2009): Si and O diffusion in (Mg,Fe)2SiO4 wadsleyite and ringwoodite and its implications for the rheology of the mantle transition zone. Earth Planet. Sci. Lett. 284, 103–112.

  • Dobson, DP., Dohmen, R., Wiedenbeck, M. (2008): Self-diffusion of oxygen and silicon in MgSiO3 perovskite. Earth Planet. Sci. Lett. 270, 125–129.

  • Dohmen, R. (2008): A new experimental thin film approach to study mobility and partitioning of elements in grain boundaries: Fe-Mg exchange between olivines mediated by transport through an inert grain boundary. Am. Mineral. 93, 863–874.

  • Kegler, P., Holzheid, A., Frost, D.J., Rubie, D.C., Dohmen, R., Palme, H. (2008): New Ni and Co metal-silicate partitioning data and their relevance for an early terrestrial magma ocean. Earth Planet. Sci. Lett. 268, 28–40.

  • Costa, F., Dohmen, R., Chakraborty, S. (2008): Time Scales of Magmatic Processes from Modelling the Zoning Patterns of Crystals. In: Minerals, Inclusions & Volcanic Processes, Eds.: Putirka, KD, Tepley FJ III Rev. Mineral. Geochem. 69, 545–594.

  • Dohmen, R., Becker, H-W., Chakraborty, S. (2007): Fe-Mg diffusion coefficients in olivine I: Experimental determination between 700 and 1200 °C as a function of composition, crystal orientation and oxygen fugacity. Phys. Chem. Minerals 34, 389–407. Erratum: Phys. Chem. Minerals 34, 597–598.

  • Dohmen, R., Chakraborty, S. (2007): Fe-Mg diffusion in olivine II: Point defect chemistry, diffusion mechanisms and a model for calculation of diffusion coefficients in natural olivine. Phys. Chem. Minerals 34, 409–430.

  • Milke, R., Dohmen, R., Becker, H-W., Wirth, R. (2007): Growth kinetics of enstatite reaction rims studied on nano scale, Part I: Methodology, microscopic observations and the role of water. Contrib. Mineral. Petrol. 154, 519–533.

  • Tirone, M., Ganguly, J., Dohmen, R., Langenhorst, F., Hervig, R., Becker, H-W.: (2005) Rare earth diffusion kinetics in garnet: Experimental studies and applications. Geochim. Cosmochim. Acta, 69, 2385 – 2398.

  • Costa, F., Chakraborty, S., Dohmen, R. (2003): Diffusion coupling between trace and major elements and a model for calculation of magma residence times using plagioclase. Geochim. Cosmochim. Acta 67, 2189 – 2200.

  • Dohmen, R., Chakraborty, S., Palme, H., Rammensee, W. (2003): The role of element solubility on the kinetics of element partitioning: in situ observations and a thermodynamic kinetic model. J. Geophys. Res. 108, B3, Article 2157, doi:10.1029/2001JB000587

  • Dohmen, R., Chakraborty, S. (2003): Mechanism and kinetics of element and isotopic exchange mediated by a fluid phase. Am. Mineral. 88, 1251 – 1270.

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Winter semester

  • 176 302 Introduction to Geochemistry and Mineralogy
    Bsc-level (3rd Semester): Dohmen, Schertl

  • 176 504 Kristalloptik, Gesteinsmikroskopie
    Bsc-level (5th semester): Dohmen

  • 176 742 Project in magmatic Petrology
    Msc-level (9th semester): [All staff in Petrology]

  • 176 941 Recent developments in analytical and experimental petrology
    Msc-level (9th semester): [All staff in Petrology]

  • Kolloquium, Petrology seminar
    [All staff in Petrology]

Summer semester

  • 176 405 Microscopy of rock forming minerals
    Bsc-level (4th semester): Dohmen

  • 176414 Geländeübungen Petrologie: Metamorphe Gesteine und Lagerstätten in den Ardennen
    Bsc-level (4th semester): Dohmen, Schertl

  • 176 745 Project in metamorphic petrology
    Msc-level (8th semester): [All staff in Petrology]

  • 176 943 Recent developments in igneous and metamorphic petrology
    Msc-level (8th semester): [All staff in Petrology]

  • Main Seminar Geosciences, Petrology Seminar
    [All staff in Petrology]

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  • 1999 – Dr. rer. nat. Degree, University of Cologne
    Dissertation: Gas phase as a mediator for solid-solid reactions: Knudsen cell mass spectrometry experiments and a thermodynamic kinetic modelling

  • 1996 – Physics Diploma, University of Cologne
    Thesis: Development of a computer control of a Knudsen cell mass spectrometer to investigate element fractionations in the Solar Nebula

Positions held

  • 04/2010 - present: Research Associate
    Institute for Geology, Mineralogy and Geophysics, Ruhr-University Bochum

  • 02/2009 - 03/2010: Research Associate
    Dept. of Earth Sciences, University of Bristol, United Kingdom

  • 12/1999 - 01/2009: Research Associate
    Institute for Geology, Mineralogy and Geophysics, Ruhr-University Bochum

  • 02/1996 - 10/1999: Research Assistant
    Institute for Mineralogy and Geochemistry, University to Cologne

Academic Honours

  • 1999
    Best Paper published in 1998 in American Mineralogist award, Mineralogical Society of America

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