Post-doctoral position at the GeoRessources Laboratory,
Université de Lorraine, CNRS, CREGU, Nancy - France

2-year Postdoctoral Fellowship in Metallogeny

Title: Dating of uranium deposits: reconsideration of current methodologies applied to uranium oxides and development of new isotopic approaches

The objectives

The project aims to provide new keys of understanding on the formation of uranium deposits with a specific focus on dating of these geological objects. Uranium deposits, in which U is mainly expressed as uranium oxides, are an extremely difficult geological object to date, although they could appear as a perfect case study for "classical" U-Pb dating methods with extremely high concentrations of uranium and lead. In fact, uranium oxides can easily suffer from post-crystallization alteration, and are by far less resistant than minerals like zircon or monazite. Therefore, the U-Th-Pb isotopic systems for most of the known deposits revealed strong disequilibrium features, and the geological meaning of the obtained data are highly questionable.

Based on these considerations, the present project aims to propose new geochronological tools to date uranium oxides, with a double objective of i) the reconsideration of the application of the U-Th-Pb isotopic systems and ii) the analytical development of other isotopic systems. This project will be based on both in-situ (LA-ICP-MS and SIMS) and global (MC-ICP-MS, TIMS) methods, with the aim to apply these new methods at the smallest scale possible. The work will have a significant part dedicated to tests and analytical developments, followed by applications on natural objects.

Your tasks

  • Experimental investigations of uranium oxide dissolution and elemental separation using ion exchange resins;
  • Development and application of new isotopic-based method(s) to date uranium oxides, with an objective of small scale application (in-situ and/or via microdrilling);
  • Measurements of isotopic ratios from solution and/or in-situ MC-ICP-MS, TIMS and/or SIMS;
  • reconsideration of the application of the U-Th-Pb isotopic system to uranium oxides

Your profile

You have a PhD degree in Earth Sciences or a related scientific discipline. You consider yourself as a skilled geochemist with an extended knowledge in isotope geochemistry and metallogeny. You have in-depth knowledge in mm to µm-scale mineral observation and characterization techniques, experience in clean laboratory (sample preparation from mineral dissolution, ion exchange chromatography), and measurements of isotopic ratios using solution MC-ICP-MS and/or TIMS techniques. You demonstrate a strong capability to perform experiments and developments based on new methods in isotope geochemistry.

You enjoy working in an interdisciplinary and international research environment. You consider the professional support of researchers as an opportunity to enlarge your scientific expertise and experience. Your research track record shows potential international standing and you have the capability to publish your research in highly-ranked international scientific journals.

You are enthusiastic, innovative scientist with excellent communication skills that will help to ensure your success in completing your task as a postdoctoral research scientist. You enjoy training and supervising master students, to help you fulfilling your research objectives.

We offer

Our institution is based on an interdisciplinary, innovative and dynamic collaboration. You will be part of the team "Mineral Resources" (, which gathers 15 permanent researchers, postdoctoral researchers, technicians and engineer, in addition to Master and PhD students. Our institution is the French leader academic laboratory for the study of mineral deposit formation. The institution hosts several research platforms with state-of-the-art instruments for the characterization of experimental and natural products (SEM, EMPA, LA-ICP-MS, micro-tomography, microthermometry, Raman, Infrared spectroscopy). This project will be co-realized at CRPG, Nancy (, one of the top laboratory for geochemistry research, with state-of-the-art MC-ICP-MS, TIMS and SIMS laboratories. Our institution is part of the Université de Lorraine (, which is one of the leading institutions for higher education in Europe with more than 55,000 students and 60 research laboratories. The department of Earth Sciences is one of the most important in Europe, with 4 laboratories hosting more than 300 researchers and 1000 students.

This is a full-time postdoctoral position for 24 months. The successful candidate will work in the scope of the laboratory GeoRessources, in close collaboration with CRPG laboratory and AREVA, uranium worldwide leader company. The salary will be 2300 €/month.

How to apply

Please submit your application with a Curriculum Vitae, list of publications and the name of 2 references to Dr. Julien Mercadier:, Dr. Béatrice Luais:, Dr Laurie Reisberg : Please contact Dr. Julien Mercadier (e-mail above) phone +33 3 83 68 47 48


Applications should be sent by December 31th 2016
Interviews will take place in early January 2017.
The Intended starting date is February 2017 and negotiable

posted: 22 November 2016     Please mention EARTHWORKS when responding to this advertisement.