TY - JOUR

T1 - Experimental modeling of silicate and carbonate sulfidation under lithospheric mantle P,T-parameters

AU - Zdrokov, Evgeniy

AU - Novoselov, Ivan

AU - Bataleva, Yuliya

AU - Borzdov, Yuri

AU - Palyanov, Yuri

N1 - Publisher Copyright: © 2019 by the authors.

PY - 2019/7/1

Y1 - 2019/7/1

N2 - Interactions of mantle silicates with subducted carbonates, sulfides, and sulfur-rich fluids are experimentally simulated in the olivine-ankerite-sulfur and olivine-ankerite-pyrite systems using a multi-anvil high-pressure split-sphere apparatus at 6.3 GPa and range of 1050-1550 °C. Recrystallization of Fe,Ni-bearing olivine and ankerite in a sulfur melt was found to be accompanied by sulfidation of olivine and carbonate, involving partial extraction of metals, carbon, and oxygen into the melt, followed by the formation of pyrite (±pyrrhotite), diopside, and Fe-free carbonates. The main features of metasomatic alteration of Fe,Ni-olivine by a reduced sulfur fluid include: (i) a zonal structure of crystals (Fe-rich core, Mg-rich rim); (ii) inclusions of pyrite and pyrrhotite in olivine; (iii) certain Raman spectral characteristics of olivine. At T > 1350 °C, two immiscible melts, a predominantly sulfur melt with dissolved components (or a Fe-Ni-S-O melt) and a predominantly carbonate one, are generated. The redox interaction of these melts leads to the formation of metastable graphite (1350-1550 °C) and diamond growth (1550 °C). The studied olivine-ankerite-sulfur and olivine-ankerite-pyrite interactions may be considered as the basis for simulation of metasomatic processes accompanied by the formation of mantle sulfides during subduction of crustal material to the silicate mantle.

AB - Interactions of mantle silicates with subducted carbonates, sulfides, and sulfur-rich fluids are experimentally simulated in the olivine-ankerite-sulfur and olivine-ankerite-pyrite systems using a multi-anvil high-pressure split-sphere apparatus at 6.3 GPa and range of 1050-1550 °C. Recrystallization of Fe,Ni-bearing olivine and ankerite in a sulfur melt was found to be accompanied by sulfidation of olivine and carbonate, involving partial extraction of metals, carbon, and oxygen into the melt, followed by the formation of pyrite (±pyrrhotite), diopside, and Fe-free carbonates. The main features of metasomatic alteration of Fe,Ni-olivine by a reduced sulfur fluid include: (i) a zonal structure of crystals (Fe-rich core, Mg-rich rim); (ii) inclusions of pyrite and pyrrhotite in olivine; (iii) certain Raman spectral characteristics of olivine. At T > 1350 °C, two immiscible melts, a predominantly sulfur melt with dissolved components (or a Fe-Ni-S-O melt) and a predominantly carbonate one, are generated. The redox interaction of these melts leads to the formation of metastable graphite (1350-1550 °C) and diamond growth (1550 °C). The studied olivine-ankerite-sulfur and olivine-ankerite-pyrite interactions may be considered as the basis for simulation of metasomatic processes accompanied by the formation of mantle sulfides during subduction of crustal material to the silicate mantle.

KW - Carbonate

KW - Diamond

KW - High pressure experiment

KW - Lithospheric mantle

KW - Mantle metasomatism

KW - Olivine

KW - Redox interaction

KW - Subduction

KW - Sulfidation

KW - Sulfide

KW - Sulfur

KW - mantle metasomatism

KW - lithospheric mantle

KW - HIGH-TEMPERATURE

KW - SULFUR

KW - olivine

KW - REDOX BUDGET

KW - sulfur

KW - CONSTRAINTS

KW - carbonate

KW - DIAMONDS

KW - sulfidation

KW - OLIVINE

KW - HIGH-PRESSURE

KW - SUBDUCTION

KW - high pressure experiment

KW - subduction

KW - REDUCED S

KW - diamond

KW - KAAPVAAL CRATON

KW - redox interaction

KW - sulfide

UR - http://www.scopus.com/inward/record.url?scp=85070766010&partnerID=8YFLogxK

U2 - 10.3390/min9070425

DO - 10.3390/min9070425

M3 - Article

AN - SCOPUS:85070766010

VL - 9

JO - Minerals

JF - Minerals

SN - 2075-163X

IS - 7

M1 - 425

ER -