Friday, February 10 2023, 4:10pm Geology Colloquium - GG Building 200A or via Zoom Colloquium Speaker: Jay B. Thomas Abstract: The presentation will summarize experimental research used to develop trace element thermobarometers for estimating the pressure (depth) and temperature at which rocks crystallize. I will describe two decades of research from the earliest trace element-in-mineral thermometers, problems encountered during early applications to real rocks, ensuing controversies, followed by descriptions of our recent experimental campaign that explores conditions spanning Earth’s crust through the upper mantle. I will show how we cross-check pressure and temperature estimates from our Ti-in-quartz solubility models against the widely accepted Zr-in-rutile solubility models, simple mineral reactions, and thermodynamic data. The presentation will conclude with intriguing speculation on the state of knowledge on crystallization conditions for granitic composition rocks with implications to continental crust formation. Host: Bruce Railsback This is a hybrid event, if you are unable to join us in person please join via zoom. Meeting ID: 997 2477 2096 Note: A password is required to join this meeting. Please call the Geology office (706-542-2652) and speak with a representative to obtain the code. Alternatively, a code request can be made to UGA Geology. Jay B. Thomas Professor of Petrology and Experimental Geochemistry Earth & Environmental Sciences of Syracuse University