TY - JOUR

T1 - Sulfide formation as a result of sulfate subduction into silicate mantle (Experimental modeling under high p,t-parameters)

AU - Bataleva, Yuliya

AU - Palyanov, Yuri

AU - Borzdov, Yuri

N1 - Publisher Copyright: © 2018 by the authors. Licensee MDPI, Basel, Switzerland.

PY - 2018/9/1

Y1 - 2018/9/1

N2 - Ca,Mg-sulfates are subduction-related sources of oxidized S-rich fluid under lithospheric mantle P,T-parameters. Experimental study, aimed at the modeling of scenarios of S-rich fluid generation as a result of desulfation and subsequent sulfide formation, was performed using a multi-anvil high-pressure apparatus. Experiments were carried out in the Fe,Ni-olivine–anhydrite–C and Fe,Ni-olivine–Mg-sulfate–C systems (P = 6.3 GPa, T of 1050 and 1450◦C, t = 23–60 h). At 1050◦C, the interaction in the olivine–anhydrite–C system leads to the formation of olivine + diopside + pyrrhotite assemblage and at 1450◦C leads to the generation of immiscible silicate-oxide and sulfide melts. Desulfation of this system results in the formation of S-rich reduced fluid via the reaction olivine + anhydrite + C → diopside + S0 + CO2. This fluid is found to be a medium for the recrystallization of olivine, extraction of Fe and Ni, and subsequent crystallization of Fe,Ni-sulfides (i.e., olivine sulfidation). At 1450◦C in the Ca-free system, the generation of carbonate-silicate and Fe,Ni-sulfide melts occurs. Formation of the carbonate component of the melt occurs via the reaction Mg-sulfate + C → magnesite + S0. It is experimentally shown that the olivine-sulfate interaction can result in mantle sulfide formation and generation of potential mantle metasomatic agents—S-and CO2-dominated fluids, silicate-oxide melt, or carbonate-silicate melt.

AB - Ca,Mg-sulfates are subduction-related sources of oxidized S-rich fluid under lithospheric mantle P,T-parameters. Experimental study, aimed at the modeling of scenarios of S-rich fluid generation as a result of desulfation and subsequent sulfide formation, was performed using a multi-anvil high-pressure apparatus. Experiments were carried out in the Fe,Ni-olivine–anhydrite–C and Fe,Ni-olivine–Mg-sulfate–C systems (P = 6.3 GPa, T of 1050 and 1450◦C, t = 23–60 h). At 1050◦C, the interaction in the olivine–anhydrite–C system leads to the formation of olivine + diopside + pyrrhotite assemblage and at 1450◦C leads to the generation of immiscible silicate-oxide and sulfide melts. Desulfation of this system results in the formation of S-rich reduced fluid via the reaction olivine + anhydrite + C → diopside + S0 + CO2. This fluid is found to be a medium for the recrystallization of olivine, extraction of Fe and Ni, and subsequent crystallization of Fe,Ni-sulfides (i.e., olivine sulfidation). At 1450◦C in the Ca-free system, the generation of carbonate-silicate and Fe,Ni-sulfide melts occurs. Formation of the carbonate component of the melt occurs via the reaction Mg-sulfate + C → magnesite + S0. It is experimentally shown that the olivine-sulfate interaction can result in mantle sulfide formation and generation of potential mantle metasomatic agents—S-and CO2-dominated fluids, silicate-oxide melt, or carbonate-silicate melt.

KW - Desulfation

KW - High-pressure experiment

KW - Lithospheric mantle

KW - Mantle metasomatism

KW - S-rich fluid

KW - Subduction

KW - Sulfate

KW - Sulfidation

KW - Sulfide

KW - sulfate

KW - mantle metasomatism

KW - lithospheric mantle

KW - high-pressure experiment

KW - SULFUR

KW - desulfation

KW - REDOX BUDGET

KW - ELEMENTS

KW - DIAMOND FORMATION

KW - GEOCHEMISTRY

KW - sulfidation

KW - HIGH-PRESSURE

KW - CARBON

KW - XENOLITHS

KW - subduction

KW - REDUCED S

KW - CARBIDE

KW - sulfide

UR - http://www.scopus.com/inward/record.url?scp=85052616624&partnerID=8YFLogxK

U2 - 10.3390/min8090373

DO - 10.3390/min8090373

M3 - Article

AN - SCOPUS:85052616624

VL - 8

JO - Minerals

JF - Minerals

SN - 2075-163X

IS - 9

M1 - 373

ER -