Petrostructural analysis of 31 mantle xenoliths from three kimberlitic pipes intruding the Neoproterozoic Brasilia belt close to southwestern margin São Francisco craton (SFC) reveals microstructures and compositions similar those observed in cratonic roots worldwide. (1) The spinel-peridotites sampling upper section lithospheric have dominantly refractory modal mineral compositions, whereas ga...

The oceanic crust, covering two-thirds of the Earth's surface, is formed along mid-oceanic ridges by crystallization at shallow levels melts depth partial melting mantle peridotite. Yet, process melt transport to ridge axis remains poorly understood. Ophiolites, which provide a window into uppermost mantle, contain dunite bodies often interpreted as relics flow conduits, pyroxene dissolution du...

There is growing evidence that the budget of Pb in mantle peridotites is largely contained in sulfide, and that Pb partitions strongly into sulfide relative to silicate melt. In addition, there is evidence to suggest that diffusion rates of Pb in sulfide (solid or melt) are very fast. Given the possibility that sulfide melt ‘wets’ sub-solidus mantle silicates, and has very low viscosity, the im...

Introduction: Martian (SNC) meteorites are igneous rocks that range from a reduced, trace-element depleted end member to an oxidized, trace-element enriched end member [1-3] (Figure 1). One interpretation of this trend is that relatively reduced, depleted magmas are partial melts of a reduced peridotitic mantle, whereas more oxidized, enriched magmas are mantle-derived magmas contaminated by ox...

[1] Double Wadati‐Benioff seismic zones (DSZ) with two parallel planes of seismicity separated by 15–30 km are a global feature of subduction zones in the 50–200 km depth range. Upper plane seismicity is generally attributed to dehydration of the oceanic crust but the origin of the lower seismicity plane is debated. Serpentine or hydrous‐phase dehydration embrittlement is a commonly advocated m...