Mantle Heterogeneity Recorded by Mass-Independent Fractionation of Sulfur Isotopes and Dynamic Implications
Zhang Junbo
Huang Jing
Xu Rong
Liu Yongsheng
Abstract：Sulfur is a volatile element that is prone to mass-dependent fractionation of sulfur isotopes(MDF-S)during shallow magmatic processes(e.g.,fractional crystallization and magma degassing),which limits us to constrain the properties of major mantle chemical reservoirs.The mass-independent fractionation of sulfur isotopes(MIF-S)is a phenomenon in which the fractionation behavior of sulfur isotopes deviates from the mass dependent relationship.MIF-S is mainly produced through photochemical reactions of sulfur-containing molecules under high-energy ultraviolet radiation,and its fractionation mechanism is closely related to the atmospheric evolution on early Earth.It is worth noting that MIF-S signals are commonly preserved in Archean sedimentary rocks,but they disappeared after the Great Oxidation Event(GOE).MIF-S does not rely on mantle redox states and high-temperature processes(such as partial melting,fractional crystallization,magma degassing),and can effectively avoid MDF-S driven by shallow magma processes.And so,MIF-S is crucial for understanding the onset of plate tectonics,mantle redox states,and deep material cycling.On the basis of a brief introduction to the theories of MDF-S and MIF-S,this review summarizes the sulfur isotope composition of major mantle chemical reservoirs,and focuses on the important progress in mantle heterogeneity and onset of plate tectonics recorded by MIF-S in the past two decades.
Keywords：sulfur isotopemantle heterogeneityplate tectonicsmass-dependent fractionationmass-independent fractionationgeochemistry
Publication Date：2025-07-30
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：16( 2482-2497 )