Asset Details
Do you wish to reserve the book?
Mantle wedge oxidation from deserpentinization modulated by sediment-derived fluids
Hey, we have placed the reservation for you!
By the way, why not check out events that you can attend while you pick your title.
Oops! Something went wrong.
Looks like we were not able to place the reservation. Kindly try again later.
Are you sure you want to remove the book from the shelf?
Mantle wedge oxidation from deserpentinization modulated by sediment-derived fluids
Do you wish to request the book?
Mantle wedge oxidation from deserpentinization modulated by sediment-derived fluids
Please be aware that the book you have requested cannot be checked out. If you would like to checkout this book, you can reserve another copy
We have requested the book for you!
Your request is successful and it will be processed during the Library working hours. Please check the status of your request in My Requests.
Oops! Something went wrong.
Looks like we were not able to place your request. Kindly try again later.
Journal Article
Mantle wedge oxidation from deserpentinization modulated by sediment-derived fluids
2023
Overview
High-pressure dehydration of serpentinite during subduction generates fluids that flux and melt the overlying mantle wedge, forming primary arc basalts. These basalts are substantially more oxidized than their mid-ocean ridge counterparts. At the slab surface of current subduction zones, these deserpentinization fluids are intrinsically oxidized, but, owing to the low sulfur content of subducted serpentinite, they only result in a low mantle wedge oxidation rate, which cannot account for the oxidized source of arc basalts. Here we show that infiltration of sediment-derived fluids modulates and can drastically change the oxidation capacity of deserpentinization slab fluids. The modulation of the deserpentinization oxidation capacity mostly depends on the stability and abundance of dissolved oxidized aqueous species of redox-sensitive elements—notably sulfate—and not solely on the oxidation state of the sediment. Infiltration of CH4-bearing fluids derived from graphite-bearing sediment reduces the intrinsically high oxidant capacity of deserpentinization fluids, explaining the relatively low fO2 observed in natural metaperidotite. Infiltration of sulfate-CO2-bearing, sediment-derived fluids—prevalent in modern subduction zones—generates deserpentinization fluids with a high oxidation capacity in cold and hot subduction zones, resulting in a global mantle wedge oxidation rate of 3.5 km3 yr−1. Such slab fluids will oxidize the mantle wedge at a rate similar to that of arc-basalt generation and thus account for the oxidized nature of arc volcanism.The source of highly oxidized arc magmas may rely on the infiltration of sediment-derived fluids that contain oxidized aqueous species—notably sulfate—into deserpentinization fluids, according to thermodynamic modelling.
