Office: 125A Pillsbury Hall
Lab: 261 Kolthoff Hall

Email: phasting@...
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My research interests focus on the stability of carbides in the mantle, as they may be important hosts for carbon in the deep mantle. I'm doing experiments in the system Fe-Ni-C to determine the stability of carbides as well as the solubility of C in Fe-Ni alloy. My current project involves adding 5 wt. % C to eight different starting materials (1) Fe-95 % C , (2) Ni-95% C and 6 intermediates of the Fe-C mix and Ni-C mix, where the molar Fe/(Fe+Ni) ratios are evenly spaced (0, 0.143, 0.286…… 1), performing experiments at 3 GPa and various upper mantle temperatures. The goal of this study is to model the Fe-Ni-C phase diagram.

Future work will include experiments at higher pressures (5, 7, and 9 GPa) and various lower mantle temperatures to determine the stability of carbides as well as the solubility of C in Fe-Ni alloy at lower mantle conditions, this will provide a data set that will allow us to model the changes with pressure in the Fe-Ni-C system.

These 3 GPa experiments will be performed in the 1/2" piston cylinder apparatus and analyzed with the JEOL JXA-8900 electron microprobe at the University of Minnesota. The future 5-9 GPa experiments will be performed in the Walker-style octahedral multianvil apparatus.