Sulfur is a unique element on the planet as it plays a tremendous role in controlling the behaviour of chalcophile (sulfur-loving) and siderophile (iron-loving) elements during magmatic processes. This has both geochemical and economic implications. Although the abundance of sulfur in Earth’s mantle is very low (~200 µg/g, see Sect. 2.1), sulfides are some of the most important petrogenetic agents in magmatic systems. This is because they are observed to concentrate profoundly a wide range of geochemically and economically important elements such as Cd, In, Cu, Ni, Pb, Ag, Au, and the platinum group elements (PGE). Given that sulfur is also siderophile, the largest proportion of it is concentrated in the Earth’s core, making it one of the most abundant light elements in the core (see Chap. 14 : Komabayashi et al. (2026) Sulfur in the cores of the Earth, Mars). Its exact concentration in the core is unknown, as well as whether it is in chondritic concentrations on the planet. Therefore, over the past few decades scientists have used multiple methods to estimate the concentration of sulfur in the Earth’s mantle. Most of them employed element ratios in erupted basalts; however, due to sulfur degassing this may lead to underestimated values. The concentration of sulfur in mantle rocks, however, is of primary importance and directly controls the sulfur budget during magmatic processes. Another extremely important variable is the solubility of sulfur in silicate magmas, which has strong implications for sulfide precipitation in magmatic rocks. In this chapter, we review the sulfur content and speciation in the bulk silicate Earth (BSE) and key mantle reservoirs. These include: (1) the lithospheric mantle—both MORB-producing and cratonic; (2) the asthenospheric mantle—associated with OIB and LIP magmatism, as well as the sublithospheric continental mantle; (3) the sublithospheric mantle, including the mantle transition zone and lower mantle; and (4) the mantle wedge above subducting slabs. We also review the melting regimes of sulfides in the cratonic mantle, as well as the ability of these melts to segregate and separate from the host rock, manifested by the wetting angles of sulfide melts. Since sulfides control the behaviour of noble and transition metals in magmatic processes, we briefly describe chalcophile element partitioning between sulfide and silicate liquids. We conclude by highlighting the importance of sulfur and sulfides in the mantle and magmatic processes and by making some suggestions for the directions of future research.

Sulfur and Sulfides in the Earth’s Mantle

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发表日期：

2026年

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Ekaterina S. Kiseeva,
Raúl O. C. Fonseca,
Christopher Beyer,
Yuan Li

摘要

Sulfur is a unique element on the planet as it plays a tremendous role in controlling the behaviour of chalcophile (sulfur-loving) and siderophile (iron-loving) elements during magmatic processes. This has both geochemical and economic implications. Although the abundance of sulfur in Earth’s mantle is very low (~200 µg/g, see Sect. 2.1), sulfides are some of the most important petrogenetic agents in magmatic systems. This is because they are observed to concentrate profoundly a wide range of geochemically and economically important elements such as Cd, In, Cu, Ni, Pb, Ag, Au, and the platinum group elements (PGE). Given that sulfur is also siderophile, the largest proportion of it is concentrated in the Earth’s core, making it one of the most abundant light elements in the core (see Chap. 14 : Komabayashi et al. (2026) Sulfur in the cores of the Earth, Mars). Its exact concentration in the core is unknown, as well as whether it is in chondritic concentrations on the planet. Therefore, over the past few decades scientists have used multiple methods to estimate the concentration of sulfur in the Earth’s mantle. Most of them employed element ratios in erupted basalts; however, due to sulfur degassing this may lead to underestimated values. The concentration of sulfur in mantle rocks, however, is of primary importance and directly controls the sulfur budget during magmatic processes. Another extremely important variable is the solubility of sulfur in silicate magmas, which has strong implications for sulfide precipitation in magmatic rocks. In this chapter, we review the sulfur content and speciation in the bulk silicate Earth (BSE) and key mantle reservoirs. These include: (1) the lithospheric mantle—both MORB-producing and cratonic; (2) the asthenospheric mantle—associated with OIB and LIP magmatism, as well as the sublithospheric continental mantle; (3) the sublithospheric mantle, including the mantle transition zone and lower mantle; and (4) the mantle wedge above subducting slabs. We also review the melting regimes of sulfides in the cratonic mantle, as well as the ability of these melts to segregate and separate from the host rock, manifested by the wetting angles of sulfide melts. Since sulfides control the behaviour of noble and transition metals in magmatic processes, we briefly describe chalcophile element partitioning between sulfide and silicate liquids. We conclude by highlighting the importance of sulfur and sulfides in the mantle and magmatic processes and by making some suggestions for the directions of future research.