Stijn Glorie (University of Adelaide) presents Laser ablation Lu-Hf geochronology

Stijn Glorie (University of Adelaide) presents Laser ablation Lu-Hf geochronology: a novel and robust method to rapidly date metamorphic, mafic and hydrothermal minerals
Description: Lu-Hf geochronology traditionally involves laborious chemical separation processes in specialized laboratories. The novel laser ablation approach, recently developed at the University of Adelaide (Simpson et al., 2021), enables rapid Lu-Hf isotopic data acquisition at high spatial resolution, directly from rock blocks or thin sections. Applied to garnet, the method can be conducted in a campaign-style approach to rapidly reveal the metamorphic history of a terrane and has the capability to unravel polymetamorphic histories. Apatite Lu-Hf is more robust to isotopic disturbances compared to the U-Pb system (higher closure temperature), and can be used to directly date the timing of magmatic crystallization in rocks where zircons are absent (such as mafic rocks). Apatite, as well as calcite/dolomite, fluorite and allanite are commonly associated with mineralization and can be dated by the Lu-Hf method to gain insights in hydrothermal processes. The presentation will go through a series of examples to illustrate the power of the Lu-Hf method to date a variety of geological processes that are difficult to time-constrain by other, more traditional methods.