Results 51 to 60 of about 4,719 (167)

Partial melting in the deepest mantle [PDF]

Geophysical Research Letters, 2002
We have compared the travel times of direct (P, S) and core‐reflected (PcP, ScS) phases recorded in southern Africa from earthquakes occurring in the Scotia Arc region. The low‐velocity region beneath the south Atlantic is explored by calculating ScS‐S and PcP‐P travel‐time residuals to determine the correlation and magnitude of Vs and Vp reductions in
N. A. Simmons, S. P. Grand
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Orthopyroxene-dominated upper mantle melting built the early crust of the Moon

Communications Earth & Environment
The 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, Bin Su, Shui-Jiong Wang, Yi Chen, Qiu-Li Li, Hao Wang, Hejiu Hui, Shitou Wu, Bo Zhang, Jiang-Yan Yuan   +9 more
doaj   +1 more source

CO2‐Undersaturated Melt Inclusions From the South West Indian Ridge Record Surprisingly Uniform Redox Conditions

Geochemistry, Geophysics, Geosystems, 2023
The behavior of Fe3+ during mantle partial melting strongly influences the oxidation state of the resulting magmas, with implications for the evolution of the atmosphere's oxidation state.
Yves Moussallam, Guillaume Georgeais, Estelle F. Rose‐Koga, Kenneth T. Koga, Margaret E. Hartley, Bruno Scaillet, Clive Oppenheimer, Nial Peters   +7 more
doaj   +1 more source

From the Bottom Up: Calculating Mantle‐Derived Magma Flux Using Subduction Parameters and Petrologic Constraints at Oceanic Arcs

Geochemistry, Geophysics, Geosystems
Mantle‐derived magma flux has a first‐order control on long‐term volcanic productivity, volatile cycling, and crustal growth in convergent margins. However, the factors controlling it remain unclear.
A. E. Goltz, C. B. Till, A. J. R. Kent
doaj   +1 more source

Melting of old refractory mantle during subduction initiation of the western Pacific plate

Communications Earth & Environment
The source characteristics and melting mechanisms for forearc basalts formed during subduction initiation in the western Pacific plate remain unclear.
Hong-Yan Li, Chun Yang, Marguerite Godard, Jeffrey G. Ryan, Yi-Gang Xu   +4 more
doaj   +1 more source

The Temperature and Composition of the Mantle Sources of Martian Basalts

Geophysical Research Letters, 2023
The composition of basaltic melts in equilibrium with the mantle can be determined for several Martian meteorites and in‐situ rover analyses. We use the melting model MAGMARS to reproduce these primary melts and estimate the bulk composition and ...
Max Collinet, Ana‐Catalina Plesa, Thomas Ruedas, Sabrina Schwinger, Doris Breuer   +4 more
doaj   +1 more source

Making mantle melt analogs more accurate [PDF]

Science, 2014
Geophysics![Figure][1] Hot-compressed glass structure CREDIT: D. B. GHOSH ET AL. AMERICAN MINERALOGIST 99 (JULY 2014) © MINERALOGICAL SOCIETY OF AMERICA Glasses, which can be thought of as “frozen” liquids, often are used as a proxy to study the properties of silicate melts in Earth ...
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Variable Upper Mantle Geochemical Processes Constrained From Independent Component Analysis of the Fizh Massif, Northern Oman Ophiolite

Geochemistry, Geophysics, Geosystems
We statistically analyzed the whole‐rock compositions of peridotites in the Oman ophiolite using a multivariate statistical technique called independent component analysis (ICA) to better understand the processes within the ophiolitic mantle section that
Yuto Miki, Eiichi Takazawa, Kenta Ueki, Tatsu Kuwatani   +3 more
doaj   +1 more source

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.
Dan McKenzie, Mike J. Bickle
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Lithospheric Mantle Heterogeneity Drives Delayed Magmatism and Wide Continent‐Ocean Transitions in Rifted Margins

Geophysical Research Letters
The formation of wide, magma‐starved continent–ocean transition (COT) zones remains incompletely understood. We use 2‐D thermo‐mechanical numerical experiments, coupling hydrous mantle melting with parameterized crustal accretion, to explore controls on ...
Yuan Wang, Zhonglan Liu
doaj   +1 more source