Mantle wedge control on back-arc crustal accretion

  title={Mantle wedge control on back-arc crustal accretion},
  author={Fernando Mart{\'i}nez and Brian Taylor},
At mid-ocean ridges, plate separation leads to upward advection and pressure-release partial melting of fertile mantle material; the melt is then extracted to the spreading centre and the residual depleted mantle flows horizontally away. In back-arc basins, the subducting slab is an important control on the pattern of mantle advection and melt extraction, as well as on compositional and fluid gradients. Modelling studies predict significant mantle wedge effects on back-arc spreading processes… 
Controls on back-arc crustal accretion: insights from the Lau, Manus and Mariana basins
Abstract Together, the Lau, Manus and Mariana basins encompass a broad range of conditions of back-arc basin development. Marine surveys have determined the tectonic setting and reconnaissance-scale
On the decompression melting structure at volcanic arcs and back‐arc spreading centers
Mantle dynamics can strongly affect melting processes beneath spreading centers and volcanic arcs. A 2‐D numerical model of the Tonga subduction zone, with the slab viscously coupled to the mantle
Contrasting crustal production and rapid mantle transitions beneath back-arc ridges
It is inferred that the abrupt changes in crustal properties reflect rapid evolution of the mantle entrained by the ridge, such that stable, broad triangular upwelling regions, as inferred for mid-ocean ridges, cannot form near the mantle wedge corner, and a dynamic process in which the ridge upwelled zone preferentially captures water-rich low-viscosity mantle when it is near the arc.
Iron isotopic evidence for convective resurfacing of recycled arc‐front mantle beneath back‐arc basins
Geophysical observations suggest sub‐arc convective flow transports melt‐exhausted and metasomatized wedge mantle into deeper mantle regions. Reciprocally, asthenospheric, fertile mantle may supply
Seismic evidence of effects of water on melt transport in the Lau back-arc mantle
Constraints are presented on the three-dimensional distribution of partial melt inferred from seismic velocities obtained from Rayleigh wave tomography using land and ocean-bottom seismographs to propose that the anomaly variations result from changes in the efficiency of melt extraction, with the decrease in melt to the south correlating with increased fractional melting and higher water content in the magma.
Back-arc spreading and mantle flow in the East Scotia Sea
  • R. Livermore
  • Geology
    Geological Society, London, Special Publications
  • 2003
Abstract The East Scotia Ridge exhibits systematic variations in axial morphology and basalt geochemistry. Central segments have morphology typical of intermediate-rate spreading centres and erupt
Structure of oceanic crust in back-arc basins modulated by mantle source heterogeneity
Subduction zones may develop submarine spreading centers that occur on the overriding plate behind the volcanic arc. In these back-arc settings, the subducting slab controls the pattern of mantle
The Fonualei Rift and Spreading Center: Effects of ultraslow spreading and arc proximity on back‐arc crustal accretion
Back‐arc spreading center characteristics reflect interactions between plate‐driven mantle advection and melting and slab‐driven hydrous melting and buoyant upwelling in the mantle wedge. At the
Thermochemical evolution of the sub-arc mantle due to back-arc spreading
[1] We present the results of a series of numerical geodynamic experiments designed to characterize the thermal and compositional evolution of the sub-arc mantle in response to spreading in the


Mantle flow induced by back arc spreading
Summary I present a simple model for the mantle flow induced by back arc spreading behind a subduction zone. The spreading and the subduction are represented by imposed velocities on the
Physical model of source region of subduction zone volcanics
The thermal structure of a generic subduction zone is investigated to elucidate the source region of subduction zone volcanics. The steady state thermal field is evaluated for a model subduction zone
The Geology of the Lau Basin
The Lau Basin comprises oceanic crust that separates the remnant Lau Ridge volcanic arc from the active Tofua arc. The basin is situated above mantle exhibiting strong seismic wave attenuation; it
Volcanic Episodicity and a Non‐Steady State Rift Valley Along Northeast Pacific Spreading Centers: Evidence From Sea MARC I
Sea MARC I side-looking sonar images and Sea Beam bathymetry along a 400-km stretch of the Juan de Fuca Ridge crest provide evidence that excessive extrusive volcanism periodically builds a crestal
Tonga Ridge and Lau Basin crustal structure from seismic refraction data
[1] The crustal structure across the Tonga-Lau arc-back arc system from the Lau Ridge to the Pacific Plate (178°–170°W, 18°19°S) is modeled, using data from an 840-km-long air gun refraction line
Insights into the volcanic arc mantle wedge from magnesian lavas from the Kamchatka arc
Active volcanism in the Kamchatka arc occurs where the Pacific Plate subducts beneath the Kamchatka peninsula south of its junction with the Aleutian arc. Most volcanism occurs within the Central