Dr Olivier Warr - Incorporating the full spectrum of geochronology in crustal fluids; it’s about time

In the brittle crust, low temperature reactions and processes involving host rocks and fluids drive local-global biogeochemical cycles. Providing accurate timeframes on these processes allows conversion to rates and allows temporal frameworks to be established and applied. This context means enhanced models can be generated exploring the production and accumulation of resources such as groundwaters and hydrocarbons, evaluating repositories for anthropogenic waste (nuclear, CCS), constraining subsurface biospheres, and be applied to document the local-global geochemical cycles at work in these settings. In this presentation, the spectrum of geochronologic tools used to document fluids will be examined, including short-lived isotopes (e.g. 3H, 14C, 81Kr) which are introduced at recharge and progressively decrease over time through radioactive decay, as well as radiogenic noble gases (e.g. 4He, 40Ar) which are produced and accumulate in the subsurface. In particular, this study will focus on how short-lived tracers may produce a temporal offset, but how the full spectrum of geochronologic tools can collectively be applied to provide temporal constraints and frameworks to critical subsurface processes and settings.