Dr Koen Torremans Awarded Grant of €175,866 from HORIZON 2020

Congratulations to Dr Koen Torremans (iCRAG) who has been awarded a grant of €175,866 from HORIZON 2020 for his project entitled Numerical modelling of the structural controls on Irish Zn-Pb ore deposits (MODIO)

Summary

Sustainable access to mineral resources is of critical importance to our society and has been a long-term EU objective. The world-class Irish Zn-Pb-Ag deposits comprise one of the major metallogenic provinces in the world, with over 25 economic and sub-economic deposits containing over 20 million tonnes of Zn+Pb metal. Ireland is the largest producer of Zn metal in Europe, the 4th most widely consumed metal in the world, and Pb is an essential component for car batteries, construction alloys or dyes.

The majority of the Zn-Pb ore in the Irish Lower Carboniferous rocks occurs in the hanging wall of major normal faults, replacing marine carbonates or carbonate breccias. These faults developed during Tournaisian and early Visean extensional tectonism and provided the necessary pathways for upward transport of metal-bearing fluids towards hanging wall traps where they are precipitated as Zn-Pb sulphides. These fault systems have been shown to strongly associate with the occurrence of individual orebody segments. However, despite their societal and economic importance the links between the spatial organisation of orebodies and the fault geometries is still very poorly understood, as is the evolution and timing of fault growth. Understanding the first-order structural control on these ore deposits is of great economic importance for exploitation of existing deposits and critical for predicting new deposits, given the importance of a well-connected plumbing system for metal-bearing fluids to reach their basinal traps from basement source.

MODIO therefore aims to unravel the structural controls on Irish Lower Carboniferous base metal deposits. Combining and integrating top quality data from many Irish mining industry partners and government agencies, Koen will investigate the links between the fault system framework and orebodies as well as the fundamental fault kinematics underlying the segmented extensional fault arrays that are seen to control these mineral deposits. For this, Koen will use an integrated multidisciplinary approach of (1) 3D geological modelling, (2) kinematic restoration, (3) discrete element method modelling, and (4) flexural backstripping. The project will in detail constrain the fault-mineralisation network in several Irish mineral deposits in 3D, as well as providing regional constraints. These 3D models will be used as input for forward mechanical discrete element modelling of the fault systems through time and a reconstruction of the thermal and structural evolution of the basin using flexural backstripping.

A better understanding of these fundamental issues will significantly inform mineral exploration activities and reduce investment risks in the Irish Zn-Pb deposits, and will also provide useful generic insights for the analysis and exploration of other fault-controlled mineral deposits in Europe and world-wide.

This project is funded from the European Union’s Horizon 2020 research and innovation programme under the Marie Sk?odowska-Curie grant agreement No. 745945