The proposal seeks to establish a National Geochronological Database as part of the GSI National Geoscience Data Centre, underpinned and expanded by the development of a novel in situ Rb–Sr dating protocol, made possible by reaction cell technology within the new multi-collector mass-spectrometer being commissioned at UCD. The database will be designed in consultation with GSI, iCRAG and the international geochronological community and will be populated initially by a quality-screened compilation.
The database will be underpinned by new Rb–Sr dates of feldspars and micas in Leinster granite and lithium pegmatite samples, benchmarked against existing zircon U–Pb SIMS ages for different pulses of granite intrusion and then populated by a quality-screened compilation of Irish geochronological data. The proposed Rb–Sr capability aims to expand the range of minerals amenable to precise (<2%SE) in situ dating in Ireland beyond accessory phases, allowing phases such as magmatic micas and K-feldspar, hydrothermal white mica and celadonite, and diagenetic glauconite and adularia, among others, to be dated, with manifold applications across geoscience disciplines. Visualized and disseminated alongside decades of legacy geochronological data in the proposed database, this method and project aims to reshape our approach to the fourth dimension of Irish geology.
Title: EIRbSr – Establishing a national geochronological database underpinned and expanded by a new Irish LA–ICP–MC–MS/MS Rb–Sr capability
Principal Investigator: Thomas Belgrano
Host: University City Dublin (UCD)