The Rainbow field is located on peridotite-rich mantle outcrops that are associated with emission of large amounts of CH4[40].
Thermophysical data and cross-cutting relationships support hypotheses of modification of the honeycomb terrain via vertical rise of diapirs such as ice diapirism, and the formation of the plain deposits through deposition and remobilization of an ice-rich mantle deposit.
We also speculate that the orthopyroxene-rich mantle may be formed at deep mantle wedges in the present Earth because water is being dragged into the deep mantle wedge by subducting slabs.
This, along with rich upper mantle seismic heterogeneity, suggests that mantle buoyancy and dynamics are central to present day topographic support and recent geomorphic evolution of the region.
While the continental part of New Caledonia (mainly Grande Terre) was entirely submerged during the Eocene (until 37 mya), a thick layer of heavy-metal-rich oceanic mantle accumulated [ 7].
Hydrous Na-garnet was likely formed by metasomatic reactions between Cr-rich pyrope and Na-rich aqueous fluid in the deep upper mantle.
Models based on the Voyager and Galileo measurements of Io's mass, radius, and quadrupole gravitational coefficients (numerical values related to how mass is distributed within an object) suggest that its interior is differentiated between a silicate-rich crust and mantle and an iron- or iron-sulfide-rich core.
Hydrous subducted oceanic plates are eventually dehydrated by breakdown of hydrous phases such as serpentine, lawsonite, amphiboles, and micas, and as a result, H2O-rich fluids are released in the deep upper mantle (e.g., Poli and Schmidt 1995).
Although pargasitic amphibole-rich metasomatized lithospheric mantle is excluded as the main source of the Jurassic magmas from Scania, hydrous ultramafic veins (i.e., hornblendite) may have caused subtle modifications to the compositions of passing sublithospheric melts.
This anisotropy is most probably due to a non-random distribution of crystallographic orientation of minerals in the olivine-rich ultramafic upper mantle rocks.
