Project title: Deportment of cobalt showings on the Tyrone Igneous Complex of Northern Ireland.
Researcher: Matthew Mawson
The regional tectonic history of the Caledonian terrane promotes an increased probability of success when exploring for volcanogenic massive sulphide (VMS) and orogenic gold deposit types. In 2018, quarry mapping and sampling detected disseminated sulphides with anomalous cobalt within ultramafic host rock, plus veining quartz-sulphide with anomalous cobalt. Both cobalt showings can be described as high-grade. Geochemistry of the quartz-sulphide veins detect bismuth sulfosalt mineralogy suggesting remobilisation, while copper-silver rich float shows bismuth-silica flooding. Cobalt is a major meal for the production of the battery cathode and so an important element in the world’s decarbonised future.
Recent work confirms VMS style mineralisation present within Laurentian sequences on the Tyrone Igneous Complex (TIC) and in Ireland, e.g. the Charlestown deposit. While structurally, terranes such as the Caledonian terrane experience complexity in the relationship of metasediment cover to the basement rocks, and in their tectonic processes such as basin inversion, arc development, accretion, obduction, and orogenic collapse.
The original project aims are:
• To map outcropping gabbros, alteration, intrusions, and structural features within Orritor quarry. Regional samples for thin section, and some lithogeochemical samples of main rock types.
• To identify the host rocks to mineralisation.
• To identify the main minerals host to elements of interest.
• To establish any zonation of elements with the minerals.
• To penetrate the ophiolite with a short drill hole(s) and identify lithologies within the ophiolite.
• If the above objectives are achieved, to establish if any link can be made to the regional picture: outcrops of quartz-sulphide veins high in cobalt and sulfosalts are present in adjacent lithology 5.5km to the NW (Corvanaghan quarry).