DI44A-04
The deep oxygen cycle in the early Earth
Thursday, 17 December 2015: 16:45
303 (Moscone South)
Catherine A McCammon1, Jack van Driel2, Ilya Kupenko3, Ryosuke Sinmyo4, Valerio Cerantola5, Vasily Potapkin1, Alexander I Chumakov3, Rudolf Rüffer3 and Leonid S Dubrovinsky6, (1)Bayerisches Geoinstitut, Universitaet Bayreuth, Bayreuth, Germany, (2)University College London, London, United Kingdom, (3)ESRF European Synchrotron Radiation Facility, Grenoble, France, (4)Tokyo Institute of Technology, Tokyo, Japan, (5)Bayreuth University, Bayreuth, Germany, (6)Bayerisches Geoinsitut, Bayreuth, Germany
Abstract:
Redox exchange in the deep Earth drives many of the processes and determines many of the properties involving surface reservoirs, and the differentiation and cooling that took place in the early Earth would have exerted an even greater influence. The evolving stability of bridgmanite as well as core formation incorporating light elements are but two of the many processes involving the cycling of oxygen between different Earth reservoirs in the early Earth. Laboratory studies of the relevant minerals at the appropriate pressure and temperature conditions have been pivotal in advancing our understanding of redox processes in the Earth’s interior, where iron plays a central role as the only major element with multiple electronic configurations (oxidation and spin state). Mössbauer spectroscopy has been a key player and recent developments coupling the laser heated diamond anvil cell with a synchrotron has enabled energy domain Mössbauer data on iron-containing phases to be collected in only a few hours (or less) at pressures and temperatures up to those near the Earth’s core. The presentation will showcase recent results on both quenched phases and in situ studies and discuss their implications for the deep oxygen cycle in the early Earth.
