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Hicks SP, Bie L, Rychert CA, Harmon N, Goes S, Rietbrock A, Wei SS, Collier JS, Henstock TJ, Lynch L, Prytulak J, Macpherson CG, Schlaphorst D, Wilkinson JJ, Blundy JD, Cooper GF, Davy RG, Kendall JM. Slab to back-arc to arc: Fluid and melt pathways through the mantle wedge beneath the Lesser Antilles. SCIENCE ADVANCES 2023; 9:eadd2143. [PMID: 36724230 PMCID: PMC9891694 DOI: 10.1126/sciadv.add2143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 01/04/2023] [Indexed: 06/18/2023]
Abstract
Volatiles expelled from subducted plates promote melting of the overlying warm mantle, feeding arc volcanism. However, debates continue over the factors controlling melt generation and transport, and how these determine the placement of volcanoes. To broaden our synoptic view of these fundamental mantle wedge processes, we image seismic attenuation beneath the Lesser Antilles arc, an end-member system that slowly subducts old, tectonized lithosphere. Punctuated anomalies with high ratios of bulk-to-shear attenuation (Qκ-1/Qμ-1 > 0.6) and VP/VS (>1.83) lie 40 km above the slab, representing expelled fluids that are retained in a cold boundary layer, transporting fluids toward the back-arc. The strongest attenuation (1000/QS ~ 20), characterizing melt in warm mantle, lies beneath the back-arc, revealing how back-arc mantle feeds arc volcanoes. Melt ponds under the upper plate and percolates toward the arc along structures from earlier back-arc spreading, demonstrating how slab dehydration, upper-plate properties, past tectonics, and resulting melt pathways collectively condition volcanism.
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Affiliation(s)
- Stephen P. Hicks
- Department of Earth Science and Engineering, Imperial College London, London, UK
| | - Lidong Bie
- School of Environmental Sciences, University of East Anglia, Norwich, UK
| | - Catherine A. Rychert
- School of Ocean and Earth Science, University of Southampton, Southampton, UK
- Woods Hole Oceanographic Institution, Falmouth, MA, USA
| | - Nicholas Harmon
- School of Ocean and Earth Science, University of Southampton, Southampton, UK
- Woods Hole Oceanographic Institution, Falmouth, MA, USA
| | - Saskia Goes
- Department of Earth Science and Engineering, Imperial College London, London, UK
| | | | - Songqiao Shawn Wei
- Department of Earth and Environmental Sciences, Michigan State University, East Lansing, MI, USA
| | - Jenny S. Collier
- Department of Earth Science and Engineering, Imperial College London, London, UK
| | - Timothy J. Henstock
- School of Ocean and Earth Science, University of Southampton, Southampton, UK
| | - Lloyd Lynch
- Seismic Research Centre, The University of the West Indies, St. Augustine, Trinidad and Tobago
| | - Julie Prytulak
- Department of Earth Sciences, Durham University, Durham, UK
| | | | | | - Jamie J. Wilkinson
- Department of Earth Science and Engineering, Imperial College London, London, UK
- London Natural History Museum, London, UK
| | | | - George F. Cooper
- School of Earth and Ocean Sciences, Cardiff University, Cardiff, UK
| | - Richard G. Davy
- Department of Earth Science and Engineering, Imperial College London, London, UK
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Iglesias A, Clayton RW, Pérez-Campos X, Singh SK, Pacheco JF, García D, Valdés-González C. Swave velocity structure below central Mexico using high-resolution surface wave tomography. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jb006332] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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