[SIT22-P23] Recycled Archean sulfur in the mantle wedge of the Mariana Forearc
Keywords:Multiple sulfur isotopes, Mantle heterogeneity, Serpentinite seamount, Mariana Forearc
Sulfate in the upwelling fluids show NMD (D33S ranging from −0.2‰ to −0.3‰ with analytical errors of ±0.01‰). These are unlikely to originate in typical sulfur components in the subducting plate, which is a mixture of sulfide in the MORB (D33S ≈ 0‰; Labidi et al., 2013) and sulfide produced by reduction of seawater sulfate (D33S > +0.05‰). Instead, it is comparable if Archean materials or the plume-related OIB is present in the mantle wedge beneath Mariana Forearc. Because NMD sulfur primarily originates in Archean sulfur, our results may extend the potential presence of recycled Archean materials in the upper mantle due to subduction of oceanic crusts in the Archean period or ongoing subduction of OIB seamounts abundantly exist in the Pacific Plate.
Farquhar, J., Bao, H.M., Thiemens, M., 2000. Atmospheric influence of Earth's earliest sulfur cycle. Science 289, 756-758.
Cabral, R.A., Jackson, M.G., Rose-Koga, E.F., Koga, K.T., Whitehouse, M.J., Antonelli, M.A., Farquhar, J., Day, J.M.D., Hauri, E.H., 2013. Anomalous sulphur isotopes in plume lavas reveal deep mantle storage of Archaean crust. Nature 496, 490-+.
Delavault, H., Chauvel, C., Thomassot, E., Devey, C.W., Dazas, B., 2016. Sulfur and lead isotopic evidence of relic Archean sediments in the Pitcairn mantle plume. Proceedings of the National Academy of Sciences of the United States of America 113, 12952-12956.
Labidi, J., Cartigny, P., Moreira, M., 2013. Non-chondritic sulphur isotope composition of the terrestrial mantle. Nature 501, 208-+.