Results 61 to 70 of about 338,697 (184)
The constant oxidation state of Earth’s mantle since the Hadean
Nature CommunicationsDetermining the evolutionary history of mantle oxygen fugacity (fo2) is crucial, as it controls the fo2 of mantle-derived melts and regulates atmospheric composition through volcanic outgassing. However, the evolution of mantle fo2 remains controversial.
Fangyi Zhang +6 more
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Do Olivine Crystallization Temperatures Faithfully Record Mantle Temperature Variability?
Geochemistry, Geophysics, Geosystems, 2021 Crystallization temperatures of primitive olivine crystals have been widely used as both a proxy for, or an intermediate step in calculating, mantle temperatures. The olivine‐spinel aluminum‐exchange thermometer has been applied to samples from mid‐ocean
Simon Matthews +4 more
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Re-os isotope constraints on the age of the Lithospheric mantle beneath western Greenland. [PDF]
, 2007 Alkaline magmatic activity across Western Greenland (W.G.) provides a record of lithosphere evolution over the last 600 Ma. Ultra Mafic Lamprophyre (UML) magmatism in particular has erupted an exceptional inventory of mantle xenoliths allowing a detailed
Webb, Michelle
core
Scientific Reports, 2021 Two-thirds of the Earth is covered by mid-ocean ridge basalts, which form along a network of divergent plate margins. Basalts along these margins display a chemical diversity, which is consequent to a complex interplay of partial mantle melting in the ...
Marianne Richter +4 more
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A seismological study of the mantle beneath Iceland [PDF]
, 2000 Iceland has long been thought to be underlain by a thermal upwelling, or plume, rising from deep within the mantle. This study tests this hypothesis, by a) seeking evidence for a plume in the lower mantle in azimuth anomalies at the NORSAR array and b ...
Pritchard, Matthew James +1 more
core
Mantle pseudo-isochrons revisited [PDF]
The 2.0 Ga pseudo-isochron age inferred from the mid-ocean ridge basalt 207Pb/204Pb against 206Pb/204Pb diagram is reexamined on the basis of a statistical box model of mantle processes.
Rudge, J. F.
core +1 more source
Granite magmatism and mantle filiation [PDF]
European Journal of MineralogyCurrent granite magma generation models essentially reduce to two groups: (1) intra-crustal melting and (2) basaltic origin. A mixed, crustal, and basaltic origin and therefore a mantle filiation has been proposed for most granite magma types.
M. Pichavant +3 more
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Orthopyroxene-dominated upper mantle melting built the early crust of the Moon
Communications Earth & EnvironmentThe paradigm of lunar crust formation has been widely applied to other terrestrial bodies, but the nature of early crust building on the Moon remains enigmatic.
Si-Zhang Sheng +9 more
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Geochemical Constraints on the Structure of the Earth's Deep Mantle and the Origin of the LLSVPs
Geochemistry, Geophysics, Geosystems, 2021 Geophysical analysis of the Earth's lower mantle has revealed the presence of two superstructures characterized by low shear wave velocities on the core‐mantle boundary.
Matthew Gleeson +4 more
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A eutectic parameterization of mantle melting.
Journal of Physics of the Earth, 1990 In an earlier paper the variation of melt fraction with temperature near the solidus of a rock with the composition of a garnet peridotite was parameterized as a continuous function of temperature. A number of people have suggested that eutectic melting is a better description of the behaviour near the solidus.
McKenzie, Dan, Bickle, Mike J.
openaire +2 more sources