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Article
Open AccessEvidence for suboceanic small-scale convection from a “garnet”-bearing lherzolite xenolith from Aitutaki Island, Cook Islands
Garnet peridotite xenoliths have been rarely reported from suboceanic mantle. Petrographic and geochemical characteristics of garnet-bearing oceanic peridotite xenoliths provide precious information on dynamic...
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Article
Open AccessAn automatic peak deconvolution code for Raman spectra of carbonaceous material and a revised geothermometer for intermediate- to moderately high-grade metamorphism
Carbonaceous material (CM) undergoes progressive changes that reflect its thermal history. These changes are in general irreversible and provide valuable information for understanding diagenetic and metamorphi...
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Article
Open AccessRelation between rheological properties and the stress state in subducting slabs
The distribution of different stress states in the subducting slab indicated by centroid moment tensor solutions for intra-slab earthquakes can help constrain the rheological properties of the slabs. A compari...
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Article
Open AccessClockwise rotation of SW Japan and timing of Izanagi–Pacific ridge subduction revealed by arc migration
Igneous rocks associated with the Cretaceous to Paleogene volcanic arc in SW Japan show ages that young from west to east in a direction parallel to the Median Tectonic Line suggesting corresponding translatio...
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Article
Dehydration of brucite + antigorite under mantle wedge conditions: insights from the direct comparison of microstructures before and after experiments
Hydration/dehydration of mantle peridotite significantly influences the mechanical properties at subduction zone interfaces. In particular, brucite is mechanically weak, antigorite + brucite occurs in shallow ...
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Article
Open AccessA possible mechanism for spontaneous cyclic back-arc spreading
Back-arc spreading is a non-steady-state process exemplified by the repeated cycles of spreading of the South Fiji and the Lau Basins behind the Tonga arc, and the Parece Vela Basin and the Mariana Trough behi...
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Article
Melt segregation and the architecture of magmatic reservoirs: insights from the Muroto sill (Japan)
The separation of melt from crystals is a fundamental process driving the chemical differentiation of magmas and can lead to the formation of pockets of potentially eruptible magmas in highly crystallised magm...
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Article
Open AccessSeismic evidence for flow in the hydrated mantle wedge of the Ryukyu subduction zone
It is widely accepted that water-rich serpentinite domains are commonly present in the mantle above shallow subducting slabs and play key roles in controlling the geochemical cycling and physical properties of...
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Article
Natural examples of olivine lattice preferred orientation patterns with a flow-normal a-axis maximum
Tectonic plate motion is thought to cause solid-state plastic flow within the underlying upper mantle and accordingly lead to the development of a lattice preferred orientation of the constituent olivine crystals
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Article
Paragenesis of sodic pyroxene-bearing quartz schists: implications for the P-T history of the Sanbagawa belt
Sodic pyroxene (jadeite content X jd=0.1–0.3) occurs locally as small inclusions within, albite porphyroblasts and in the matrix of hematite-bearing quartz schists in the Sanbagawa (Sambagawa) metamorphic belt, c...
