Mobilization of isotopically heavy sulfur during serpentinite subduction.

ABSTRACT: Primitive arc magmas are more oxidized and enriched in sulfur-34 (³⁴S) compared to mid-ocean ridge basalts. These findings have been linked to the addition of slab-derived volatiles, particularly sulfate, to arc magmas. However, the oxidation state of sulfur in slab fluids and the mechanisms of sulfur transfer in the slab remain inconclusive. Juxtaposed serpentinite and eclogitic metagabbro from the Voltri Massif (Italy) provide evidence for sulfur mobilization and associated redox processes during infiltration of fluids. Using bulk rock and in situ δ³⁴S measurements, combined with thermodynamic calculations, we document the transfer of bisulfide-dominated, ³⁴S-enriched fluids in equilibrium with serpentinite into adjacent metagabbro. We argue that the proc

SUBMITTER: Schwarzenbach EM 

PROVIDER: S-EPMC11305377 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature