Testing deformation-enhanced element mobility in plagioclase
Naomi Barshi, John Abbott College/McGill University
Christie Rowe, McGill University
Vincent van Hinsberg, McGill Universtiy
I present an update on strain-enhanced diffusion in plagioclase through a multiscale theoretical and physical approach. I combined field-scale, thin-section scale, and grain-scale strain and chemical measurements for major and trace elements in naturally deformed plagioclase phenocrysts. I conclude that at low strain and low compositional contrast between primary growth zones, the effect of strain-enhanced element mobility, as predicted from my model, is too subtle to quantify using available analytical techniques. For these conditions, a static diffusion model is sufficient, and geothermobarometers and geochronometers can still be applied to yield accurate results.