- Postgraduate Researcher
Hilde Koch is a PhD researcher in the iCRAG raw materials research spoke. She graduated in 2016 with BSc and MSc degrees from the University of Tuebingen. For her MSc, she specialised in isotope geochemistry. In 2016, Hilde joined the iCRAG team under the supervision of Prof. Balz Kamber at Trinity College Dublin. Her research focuses on the chemistry of Irish Mississippian bentonite layers and the carboniferous limestones in between. Hilde investigates how they could be used as stratigraphic and tectonic markers relevant for the zinc – lead deposits of Ireland. Her research involves high – precision trace element geochemical methodology, as well as Sr isotopic studies.
Ireland hosts a large number of zinc-lead deposits, of which one is currently exploited at Navan. This mine is Europe’s largest zinc producer. The search for additional economic deposits is ongoing. So far, in the Irish ore field there is information missing which could clarify the timing and the position of mineral deposits. Bentonite layers are volcanic ash beds which form widespread deposits. The position of these volcanic layers relative to the zinc – lead deposits of Ireland makes them useful markers, which can be indicative of the presence of zinc-lead deposits. These volcanic layers can show recognizable patterns in diagnostic elements, which characterise the layers and therefore make them distinguishable. Additionally, the chemistry of the ore hosting rock can be used as a secondary marker to test the results from the bentonite layers.
Project title: The chemostratigraphy and petrology of Mississippian volcanogenic clay bands (tuffs) in the Irish Midlands and their relation to potential volcanic centers
There are various volcanogenic clay bands of Mississippian age which occur in the Irish Midlands. Their relative position to the zinc – lead deposits of Ireland makes them extremely important stratigraphic and tectonic markers. The aim of the project is to develop a chemical stratigraphy for the Irish Mississippian bentonite layers and the host carboniferous limestones. With the help of the markers we will be able to clarify stratigraphic correlations and hence the timing of faulting and associated mineralisation.
The first task of the study is to focus on the stratigraphy in and around the Navan ore body. The second component is a regional chemostratigraphic survey of the Irish Midlands. Furthermore, it is proposed that a petrological and geochemical characterisation of the volcanic centres will be undertaken in collaboration with FI Emma Tomlinson.
The research involves major element analysis by ICP-OES, high–precision trace element geochemical methodology using solution ICP-MS as well as Sr isotope measurements. Additionally, a laser ablation ICP-MS method will be developed using the laser as a micromill. Sr isotopes will be measured with a multi-collector mass spectrometer at UCD.
- Postgraduate Researcher
- Earth Resources
- Critical Materials