Session outline

Solid Earth Sciences(S) Session Sub Category Complex & General(CG) Session ID S-CG19 Title Hydrogen in the Earth's interior from the crust to the core Short title Hydrogen in the Earth's interior Convener Name Bjorn Mysen Affiliation Geophysical Laboratory, Carnegie Inst. Washington Co-convener 1. Name Eiji Ohtani Affiliation Department of Earth and Planetary Materials Science, Graduate School of Science, Tohoku University Co-convener 2. Name Toru Inoue Affiliation Geodynamics Research Center, Ehime University International Symposium 'International Symposium' in addition to Scientific session. Language English Scope Hydrogen-rich volatiles are critical partners of the dynamic Earth. They play a central role throughout the Earth's interior from shallow hydrothermal systems in oceanic and subduction zone settings, in zones of mantle melting, at the fluid-enriched slab/upper mantle interface, in the mantle transition zone and lower mantle to the core-mantle boundary, and the Earth's core. This session will focus on how hydrogen-rich volatiles affect the geochemistry, mineralogy, and geophysics of the Earth's interior through natural observations, laboratory experiments, and numerical modeling. H2O dominates in most settings in the present Earth. H2 is found in shallow hydrothermal environments resulting from alteration of ultramafic rocks. Molecular H2 and hydrogen-bearing reduced nitrogen and carbon species (i.e, methane and ammonia) can be dominant in the deep mantle. Hydrides are candidates for core components. Water, H2, and CH4 were the principal species in the silicate Earth during the first few million years of its history. Hydrogen-containing fluids, melts, and minerals affect mineralogy, phase relations, and numerous other physical and chemical properties and processes in the Earth's interior. Characterization of these processes is accomplished by combining observation, experiment and modeling. To this end, this session will include discussion of (i)How volatiles control the Earth's dynamic processes including recycling and mass transfer processes, (ii) Stability relations, chemical and physical properties of hydrous and hydride crystalline and molten phases and application of such information to geophysical properties, including seismic behavior, of the Earth's interior, (iii) Hydrogen solubility in oxides and metals at deep earth interior conditions and its effect on mantle rheology and equation-of-state, and (iv) Hydrogen and melt crystallization and element distribution and redistribution in the silicate Earth. Type of presentation Oral and Poster presentation Invited papers Jie Li(University of Michigan) Hugh O'Neill(Australian National University) Charles LELOSQ (Australian National University) Razvan Caracas (Ecole Normale Superieure, Lyon)