The themes central to our current research are:
The nature and origin of tectonic shuffle zones
These are large-scale movement zones that reverse their shear sense during orogenesis, with relative displacements that potentially can exceed 100-200 km.
The thin exotic lenses that can be stranded in such zones often have a distinctive history of pressure and temperature, and argon geochronology has proven essential in their analysis.
The approach and methodology used to date movements through microstructures
All too often in the past people have grabbed rocks, crushed them up, and tried to guess what the ages obtained happend to mean. This has not been a successful line of endeavour.
Now, with painstaking attention t detail, microstructuraly focussed argon geochronology is providing temporal constraints on movement through microstructure.
It is a powerful tool that can constrain the duration of thermal events associated with deformation and metamorphism, even in very old samples. The difficulty is that the method requires accurate determination of the diffusion parameters for potassium-bearing minerals, and an ability to quantify the influence exerted by an evolving microstructure.
Combining Advanced Microscopy with microstructuraly focussed argon geochronology offers a way forward, and we are now making considerable headway in respect to timing the duration of metamorphic events in classical Barrovian terranes.