January 30, 2019
OSU's Brendan Hanger to present geology seminar Jan. 31
Brendan Hanger, teaching assistant professor in the Boone Pickens School of Geology at Oklahoma State University, will present a geology seminar at 4 p.m. Thursday, Jan. 31, in 213 Thompson Hall. The title of his presentation is "The Story of One Garnet: Mantle Redox, Metasomatism and Kimberlite Ascent."
Hanger's focus is on igneous and metamorphic petrology, mineralogy, introductory and field geology. Before arriving at OSU in 2017, he taught as teaching fellow at the Australian National University, where he completed a doctorate in mantle petrology in 2014. Previously, he earned a Bachelor of Science in geology-honours from Australian National University and a Bachelor of Science in geology/chemistry) and Bachelor of Engineering in chemical-honours from Monash University, Melbourne, Australia.
Abstract: Due to ability to host Fe in multiple valence states, garnet in peridotite allows us to explore the redox state of the mantle at high resolution. This talk will explain one single garnet crystal was able to document the redox conditions, metasomatic history and eruption timing for the Wesselton kimberlite in South Africa. Electron microprobe and LA-ICP-MS analyses were used in conjunction with synchrotron X-ray Absorption Near-Edge Structure, or XANES, spectroscopy and NanoSIMS to measure major elements, trace elements, Fe speciation and quantify diffusion time frames, all of which allowed an extremely detailed investigation of the history of the cratonic mantle.