Results 91 to 100 of about 59,876 (275)

New knowledge about shock events that affected the L‐chondrite parent body from two heavily shocked L6 meteorite finds

Meteoritics &Planetary Science, EarlyView.
Abstract We report new results from a study of shock‐related features in the L6 ordinary chondrites Northwest Africa (NWA) 4672 and NWA 12841. Our observations confirm the occurrence of eight high‐pressure (HP) minerals in each meteorite, namely, ringwoodite, majorite, akimotoite, wadsleyite, albitic jadeite, lingunite, tuite, and xieite.
I. Baziotis, L. Ferrière, C. Ma, J. Hu, D. Palles, P. D. Asimow   +5 more
wiley   +1 more source

Noble gases and nitrogen in material from asteroid Bennu

Meteoritics &Planetary Science, EarlyView.
Abstract We report the elemental and isotopic abundances of all stable noble gases (helium, neon, argon, krypton, and xenon) in eight particles from asteroid Bennu returned by NASA's OSIRIS‐REx mission. We also report nitrogen abundances and isotopic ratios that were analyzed alongside neon and argon in four additional Bennu particles.
B. Marty, L. Zimmermann, E. Füri, D. V. Bekaert, J. J. Barnes, A. N. Nguyen, H. C. Connolly, D. S. Lauretta   +7 more
wiley   +1 more source

Moon's volcanic history revealed in glassy spherules from Apollo 17 soil 76501

Meteoritics &Planetary Science, EarlyView.
Abstract Rapidly quenched droplets of pyroclastically erupted lava are common in lunar regolith at landing sites proximal to the maria. Here, we document the U‐Pb chronologies, major element, and trace element compositions of picritic glassy particles from Apollo 17 regolith sample 76501. These particles are dominated by high‐Ti compositions similar to
Alexander A. Nemchin, Marc D. Norman, Martin J. Whitehouse, Evgenia Salin, Nicholas E. Timms, Tao Long, Xiaochao Che, Renaud Merle, Fred Jourdan, Tao Luo   +9 more
wiley   +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 ...
openaire   +1 more source

Two-sided asymmetric subduction; implications for tectonomagmatic and metallogenic evolution of the Lut Block, Eastern Iran [PDF]

, 2011
West directed subduction zones show common characteristics, such as low structural elevation, deep trench, steep slab and a conjugate back-arc basin that are opposite to those of the east directed subduction zones.
Arjmandzadeh, R., Homam, S. M., Karimpour, M. H., Mazaheri, S. A., Medina, J. M., Santos, J. F.   +5 more
core   +2 more sources

Melting and Mixing States of the Earth's Mantle after the Moon-Forming Impact [PDF]

, 2015
The Earth's Moon is thought to have formed by an impact between the Earth and an impactor around 4.5 billion years ago. This impact could have been so energetic that it could have mixed and homogenized the Earth's mantle. However, this view appears to be
Nakajima, Miki, Stevenson, David J.
core   +4 more sources

Substitution of Fe3+ into anorthite in oxidized, Al‐deficient ferrobasaltic systems with implications for the petrogenesis of angrite meteorites

Meteoritics &Planetary Science, EarlyView.
Abstract Angrite meteorites are critically silica‐undersaturated igneous rocks with high Ca/Al and Fe/Mg, along with depletion in volatile lithophile elements Na and K such that they crystallize anorthite along with olivine and calcic pyroxene. The anorthite in angrites contains substantial Fe, and in NWA 1670 and NWA 1296, it is present at major ...
Seann J. McKibbin, Dominique Tanner, Hugh St. C. O'Neill   +2 more
wiley   +1 more source

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
openaire   +2 more sources

Chemical differentiation of a convecting planetary interior: Consequences for a one-plate planet such as Venus [PDF]

Chemically depleted mantle forming a buoyant, refractory layer at the top of the mantle can have important implications for the evolution of the interior and surface.
Hess, P. C., Parmentier, E. M.
core   +1 more source