HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Journal articles

Solid-phase transfer into the forearc mantle wedge: Rutile and zircon xenocrysts fingerprint subducting sources

Abstract : Voluminous flux of a hydrous component from subducting oceanic lithosphere into the forearc mantle and its contribution to arc magmas have long been recognised but the transfer of solid-phase materials has received less consideration. Although xenocrystic zircons are known from some arc magmas and ophiolitic chromitites their origins remain enigmatic. How and when such materials are transferred into the overlying wedge of mantle lithosphere and the length of their residency therein are unclear. Using zircons and rutiles recovered from ophiolitic rocks in New Caledonia, we demonstrate unambiguous association with subducting sediments and hence evidence for inter-plate transfer. The 'fingerprints' of age spectra for both minerals can be matched to lithospheric slab components subducted during Eocene time. Their occurrence in forearc harzburgite suggests that they were incorporated into their mantle wedge host at subduction depths beyond the onset of serpentinisation at ca. 300 • C but before the ca. 600 • C destabilisation temperature of the rutile U-Pb system. Relocation from slab to forearc mantle is therefore likely to have occurred at ca. 50-60 km depth within the subduction channel. Fluid-assisted conveyance of high field strength elements within solid-state accessory mineral phases into suprasubduction mantle wedges may represent a little-recognised but significant phenomenon that is both predictable and pervasive at convergent margins globally.
Complete list of metadata

https://hal-cnrs.archives-ouvertes.fr/hal-03510734
Contributor : Dominique Cluzel Connect in order to contact the contributor
Submitted on : Tuesday, January 4, 2022 - 4:00:42 PM
Last modification on : Tuesday, January 18, 2022 - 3:30:04 AM

File

AitchisonEtAl_Xenocrystic zirc...
Publisher files allowed on an open archive

Identifiers

Collections

CNRS | UNC

Citation

Jonathan Aitchison, Dominique Cluzel, Trevor Ireland, Renjie Zhou, Dongyang Lian, et al.. Solid-phase transfer into the forearc mantle wedge: Rutile and zircon xenocrysts fingerprint subducting sources. Earth and Planetary Science Letters, Elsevier, 2022, 577, pp.117251. ⟨10.1016/j.epsl.2021.117251⟩. ⟨hal-03510734⟩

Share

Metrics

Record views

10

Files downloads

2