Slab steepening and rapid mantle wedge replacement during back-arc rifting in the New Hebrides

Haase K, Regelous M, Beier C, Koppers AA (2024)

Publication Type: Journal article

Publication year: 2024

Journal

Nature Communications Nature Publishing Group: Nature Communications

Book Volume: 15

Article Number: 6070

Journal Issue: 1

DOI: 10.1038/s41467-024-50445-3

Abstract

The effects of the composition and angle of the subducting slab and mantle wedge flow on tectonic and magmatic processes in island arcs and associated back-arcs are poorly understood. Here we analyse the ages and compositions of submarine lavas from the flanks and the floor of the back-arc Futuna Trough some 50 km east of Tanna Island in the New Hebrides arc front. Whereas >2.5 Ma-old back-arc lavas formed from an enriched mantle source strongly metasomatized by a slab component, the younger lavas show less slab input into a depleted mantle wedge. The input of the slab component decreased over the past 2.5 million years while the enriched mantle was replaced by depleted peridotite. The change of Futuna Trough lava compositions indicates rapid (10 s of km/million years) replacement of the mantle wedge by corner flow and slab steepening due to rollback, causing extensional stress and back-arc rifting in the past 2.5 million years.

Authors with CRIS profile

Karsten Haase Lehrstuhl für Endogene Geodynamik Marcel Regelous Geozentrum Nordbayern

Involved external institutions

Helsingin yliopisto / University of Helsinki

Finland (FI) Oregon State University (OSU)

United States (USA) (US)

How to cite

APA:

Haase, K., Regelous, M., Beier, C., & Koppers, A.A. (2024). Slab steepening and rapid mantle wedge replacement during back-arc rifting in the New Hebrides. Nature Communications, 15(1). https://doi.org/10.1038/s41467-024-50445-3

MLA:

Haase, Karsten, et al. "Slab steepening and rapid mantle wedge replacement during back-arc rifting in the New Hebrides." Nature Communications 15.1 (2024).

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