About this Abstract |
Meeting |
5th International Congress on 3D Materials Science (3DMS 2021)
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Symposium
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5th International Congress on 3D Materials Science (3DMS 2021)
|
Presentation Title |
Phase Change of Pyrolitic Material: In-situ Transformation and Induced Microstructures at 660 km Depth |
Author(s) |
Jeff Gay, Estelle Ledoux, Matthias Krug, Anna Pakhomova, Ilya Kupenko, Julien Chantel, Carmen Sanchez-Valle, Sébastien Merkel |
On-Site Speaker (Planned) |
Jeff Gay |
Abstract Scope |
Phase transformations within the Earth’s mantle can cause crystal growth in preferred orientations among other phenomena. These phase changes are a result of changes in pressure and temperature with depth. At 660 km, ringwoodite and garnet decompose to form bridgmanite and ferropericlase. These transformations generate microstructures, cause seismic reflectors, and viscosity changes that impact mantle dynamics. Understanding these transformation microstructures will hence better constrain processes in the Earth’s mantle. These transformations are not martensitic, but grains grow with preferred orientations through diffusive processes.
Here we implement synchroton multigrain x-ray diffraction in a laser heated diamond anvil cell. We are able to track individual grains, crystal structures, and orientations, while being compressed in-situ at pressures ranging from 18 to 55 GPa and temperatures of ~1800 K. Using this experimental approach, we can then use obtained transformation textures to refine current seismic models to better understand seismic observables in the Earth’s mantle. |
Proceedings Inclusion? |
Definite: Other |