Findings of coesite and microdiamond in metamorphic rocks of supracrustal protolith led to the recognition of continental subduction to mantle depths. The crust-mantle interaction is expected to take place during subduction of the continental crust beneath the subcontinental lithospheric mantle wedge. This is recorded by postcollisional mafic igneous rocks in the Dabie-Sulu orogenic belt and it...

It is possible that the majority of Earth’s H2O budget is present as hydroxyl (OH) structurally incorporated into the major nominally anhydrous minerals (NAMs) of the mantle (e.g., Martin and Donnay 1972). Ringwood (1966) thought as much as fi ve times the surface H2O-mass could be present in the mantle, amounting to ~0.2 wt% H2O if distributed throughout the entire mantle (Harris and Middlemos...

The Atlas Mountains of Morocco display high topography, no deep crustal root, and regions of localized Cenozoic alkaline volcanism. Previous seismic imaging and geophysical studies have implied a hot mantle upwelling as the source of the volcanism and high elevation. However, the existence, shape, and physical properties of an associated mantle anomaly are debated. Here we use seismic waveform ...

Mantle-derived xenoliths brought to the Earth’s Surface by basalts are important windows to understand composition, evolution and processes of the lithospheric mantle. The lithosphere of the southeastern China is dominated by peridotite or lherzolite [1, 2]. The spinel peridotite xenoliths studied are from Fangshan basalt, eastern China, which are composed of olivine, clinopyroxene, orthopyroxe...

Mantle plumes are thought to play a key role in transferring heat from the core-mantle boundary to the lithosphere, where it can significantly influence plate tectonics. On impinging on the lithosphere at spreading ridges or in intra-plate settings, mantle plumes may generate hotspots, large igneous provinces and hence considerable dynamic topography. However, the active role of mantle plumes o...

We have reexamined the role played by transient rheology in the interpretation of mantle viscosity. This investigation has been carried out by comparing the amplitude responses with the data of secular variation of J2, the relative sea-level histories at sites well within the ice margins and at the ice margin like the city of Boston. A linear Burgers' body theology has been assumed in the lower...

Mineral properties in Earth's lower mantle are affected by iron electronic states, but representative pressures and temperatures have not yet been probed. Spin states of iron in lower-mantle ferropericlase have been measured up to 95 gigapascals and 2000 kelvin with x-ray emission in a laser-heated diamond cell. A gradual spin transition of iron occurs over a pressure-temperature range extendin...

[1] Numerical mantle convection models indicate that subducting slabs can reach the core-mantle boundary (CMB) for a wide range of assumed material properties and plate tectonic histories. An increase in lower mantle viscosity, a phase transition at 660 km depth, depth-dependent thermal expansivity, and depth-dependent thermal diffusivity do not preclude model slabs from reaching the CMB. We fi...

D′′ (Dee double prime), the lowermost layer of the Earth’s mantle, is the thermal boundary layer (TBL) of mantle convection immediately above the Earth’s liquid outer core. As the origin of upwelling of hot material and the destination of paleoslabs (downwelling cold slab remnants), D′′ plays a major role in the Earth’s evolution. D′′ beneath Central America and the Caribbean is of particular g...

The "acid mantle" is a topic not only of historical interest, but also of clinical significance and has recently been linked to vital stratum corneum function. Despite compelling basic science evidence placing skin pH as a key factor in barrier homeostasis, stratum corneum integrity, and antimicrobial defense, application of the acid mantle concept in clinical care is lacking. We review recent ...