Fully funded PhD Studentship: The iron isotopic composition of hanging wall pyrite in sediment hosted Zn deposits

School of Earth Sciences, University College Dublin, Ireland and
German Centre for Geosciences, Potsdam, Germany

Project background and description:

In Zn-mineralised sedimentary basins, pyrite is spatially associated with Zn mineralisation and where it is stratiform it can be imaged by geophysical methods and used for drill-hole targeting. Most commonly, pyrite is found in the hanging wall and the total abundance of this pyrite is higher proximal to high grade Zn mineralisation. Some researchers interpret that this pyrite is hydrothermal and can form a distal halo around a potential deposit (e.g. Large et al., 2005). However, more recent S isotope work suggests that stratiform pyrite may also be diagenetic, formed by microbial sulfate reduction, and therefore pre-date the hydrothermal system (e.g., Magnall et al., 2020; Rieger et al., 2020).

The source of the Fe which forms the hanging wall pyrite is unknown (e.g., how much of it is hydrothermal and derived from the basement or underlying sequences; how much is stripped from the basinal sediments during hydrothermal fluid flow or diagenesis; how much comes from seawater?). We will investigate this by measuring δ 56 Fe values in barren and mineralised hanging-wall pyrite samples from Paleoproterozoic deposits in the MacArthur and Mt Isa Basins (Australia), the Carboniferous Annaraaq deposit (Alaska) and the Late Devonian Tom, Jason and Boundary Zone deposits (Canada). We will then assess the source of the iron in the hanging wall pyrite and whether there is a change in isotopic composition proximal to mineralisation. The student will also work on the Carboniferous Irish-type deposits and will collect samples of the Old Red Sandstone and the greywackes in the basement under the deposits and measure their composition, including the bulk Fe isotope values (Johnson et al., 2008). We will then analyse δ 56 Fe values in pyrite samples (Lin et al., 2017) from the Irish Orefield (leveraging ongoing work by Dr. Claire Geel, UCD). The work will dominantly be carried out in the National Centre for Isotope Geochemistry at UCD and will require working in a clean lab to carry out sample digestion and purification followed by isotope measurements using a Neoma MS/MS-MC-ICP-MS in collaboration with colleagues in the School of Earth Sciences.

The successful applicant will be based at the School of Earth Sciences, University College Dublin (UCD), where they will work together with Prof. Sarah A. Gleeson (primary supervisor), and Dr. Edith Kubrik (co-supervisor). The project will also be co-supervised by Dr. Joe Magnall at the GFZ in Potsdam, Germany.

Requirements/ Person specification:

Applications are invited from students who can demonstrate an excellent background in geochemistry, mineralogy, isotopic analyses. Passion for laboratory work, as well as willingness to be involved in technique development is essential and self-motivation for solving problems is essential. Candidates must have obtained a relevant geoscience honours degree or (ideally) a geoscience MSc degree. Applicants must have demonstrated experience in scientific writing and giving scientific presentations. Please check that you meet the academic and English language requirements for the position as outlined at .

Award:

This project is funded by a Research Ireland Research Professorship to Prof. Sarah A. Gleeson. The Gleeson group will comprise 13 researchers. The successful candidate will be enrolled for a 48-month (Structured) PhD programme at University College Dublin, Ireland. The studentship provides university tuition fees and an annual tax-free stipend of €25,000 over four years. Funds for project costs are also available.

Start date:

The start date is on the 2 nd of January 2026.

Further information:

For further information on the application process please contact Ms. Ana Luisa Lavado ( [email protected] ) and for technical aspects of the project, Prof. Sarah A. Gleeson (Email: [email protected] ).

Application procedure:

If interested, please apply by sending an e-mail containing (in PDF-format): (1) a full CV (when applicable including a publication list), (2) a cover letter stating why you are interested in this project, and why you are the ideal candidate for this position, and (3) the names and contact details of two academic referees, to Ms. Ana Luisa Lavado ( [email protected] ).

Closing date:

The closing date for applications is 12:00 noon (local Irish time) on the 12 December 2025 .