Research output: Contribution to journal › Article › peer-review
The reactions between iron and magnesite at 6 GPa and 1273-1873 K : Implication to reduction of subducted carbonate in the deep mantle. / Martirosyan, Naira S.; Litasov, Konstantin D.; Shatskiy, Anton et al.
In: Journal of Mineralogical and Petrological Sciences, Vol. 110, No. 2, 2015, p. 49-59.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - The reactions between iron and magnesite at 6 GPa and 1273-1873 K
T2 - Implication to reduction of subducted carbonate in the deep mantle
AU - Martirosyan, Naira S.
AU - Litasov, Konstantin D.
AU - Shatskiy, Anton
AU - Ohtani, Eiji
PY - 2015
Y1 - 2015
N2 - The interaction between Fe-metal and magnesite was studied in multianvil experiments at 6 GPa and 1273-1873 K using different capsule materials: Fe, BN, and MgO. It was observed that at subsolidus conditions reaction proceeds with the formation of Fe3C and magnesiowüstite in the stoichiometric proportions according to relation: MgCO3 + 5Fe = 3(Fe0.66Mg0.33)O + Fe3C. At melting conditions (1673-1873 K) magnesite and iron react in nearly equivalent molar proportions with formation of Mg-Fe-carbonatite melt, Fe-C alloy, magnesiowüstite and graphite. The reactions clearly show that free carbon and metallic iron phases cannot coexist in the upper mantle and presumably in transition zone and will always form Fe-carbide. The carbon content in Fe-C alloy and its coexistence with diamond will be strongly dependent on the oxygen fugacity. The studied reactions can be considered as intermediate processes in the reduced mantle domains at the contact with submerging subduction slabs and have further implication to the processes at the core-mantle boundary.
AB - The interaction between Fe-metal and magnesite was studied in multianvil experiments at 6 GPa and 1273-1873 K using different capsule materials: Fe, BN, and MgO. It was observed that at subsolidus conditions reaction proceeds with the formation of Fe3C and magnesiowüstite in the stoichiometric proportions according to relation: MgCO3 + 5Fe = 3(Fe0.66Mg0.33)O + Fe3C. At melting conditions (1673-1873 K) magnesite and iron react in nearly equivalent molar proportions with formation of Mg-Fe-carbonatite melt, Fe-C alloy, magnesiowüstite and graphite. The reactions clearly show that free carbon and metallic iron phases cannot coexist in the upper mantle and presumably in transition zone and will always form Fe-carbide. The carbon content in Fe-C alloy and its coexistence with diamond will be strongly dependent on the oxygen fugacity. The studied reactions can be considered as intermediate processes in the reduced mantle domains at the contact with submerging subduction slabs and have further implication to the processes at the core-mantle boundary.
KW - Carbonate
KW - High-pressure experiment
KW - Iron
KW - Mantle
KW - Subduction
UR - http://www.scopus.com/inward/record.url?scp=84928894242&partnerID=8YFLogxK
U2 - 10.2465/jmps.141003a
DO - 10.2465/jmps.141003a
M3 - Article
AN - SCOPUS:84928894242
VL - 110
SP - 49
EP - 59
JO - Journal of Mineralogical and Petrological Sciences
JF - Journal of Mineralogical and Petrological Sciences
SN - 1345-6296
IS - 2
ER -
ID: 25793222