Results 61 to 70 of about 16,936 (226)

Long‐Lasting Volcanism of the Moon Aided by the Switch in Dominant Mechanisms of Magma Ascent: Role of Localized Radioactive Enrichment in a Numerical Model of Magmatism and Mantle Convection

Geophysical Research Letters
Significant volcanic activity continued for billions of years since 3.5–4 Gyr ago in the Procellarum KREEP Terrane (PKT) of the Moon, but not so significant outside the PKT.
Ken'yo U, Masanori Kameyama, Gaku Nishiyama, Takehiro Miyagoshi, Masaki Ogawa   +4 more
doaj   +1 more source

Low-degree mantle convection with strongly temperature- and depth-dependent viscosity in a three-dimensional spherical shell

, 2005
A series of numerical simulations of thermal convection of Boussinesq fluid with infinite Prandtl number, with Rayleigh number $10^7$, and with the strongly temperature- and depth- dependent viscosity in a three-dimensional spherical shell is carried out
Akira Kageyama, Breuer, Bunge, Bunge, Bunge, Davies, Hager, Hansen, Harder, Harder, Harder, Kageyama, Konopliv, Masaki Yoshida, McNamara, Phillips, Rappaport, Ratcliff, Ratcliff, Ratcliff, Reese, Schubert, Schubert, Sleep, Smith, Smith, Solomatov, Solomatov, Stemmer, Tackley, Tackley, Trompert, Wessel, Yoshida, Yoshida, Zhang, Zhong, Zhong, Zhong   +38 more
core   +1 more source

Timing of Metamorphism and Deformation in the Neoarchean Quetico Metasedimentary Belt, Superior Craton, Constrained by Garnet Trace‐Element Mapping and Lu–Hf Geochronology

Journal of Metamorphic Geology, EarlyView.
ABSTRACT The Quetico subprovince of the Superior Province is among the largest metasedimentary belts globally and provides evidence of tectonic processes at play during the final stages of Archean cratonization. Although previous studies have shown that deformation and metamorphism of the 2.7‐Ga turbiditic protolith resulted in regional subvertical ...
Adrian G. Rehm, Antoine Godet, Doug Tinkham, Carl Guilmette, Matthijs A. Smit   +4 more
wiley   +1 more source

Mantle roots of the Emeishan plume: an evaluation based on teleseismic P-wave tomography [PDF]

Solid Earth, 2017
The voluminous magmatism associated with large igneous provinces (LIPs) is commonly correlated to upwelling plumes from the core–mantle boundary (CMB). Here we analyse seismic tomographic data from the Emeishan LIP in southwestern China.
C. He, M. Santosh, M. Santosh
doaj   +1 more source

The elastic constants of MgSiO3 perovskite at pressures and temperatures of the Earth's mantle

, 2009
The temperature anomalies in the Earth's mantle associated with thermal convection1 can be inferred from seismic tomography, provided that the elastic properties of mantle minerals are known as a function of temperature at mantle pressures.
AR Oganov, Artem R. Oganov, BB Karki, BLN Kennett, C Cavazzoni, C da Silva, D Alfé, DA Yuen, DC Wallace, DL Anderson, E Knittle, F Ancilotto, F Buda, G Kresse, G Masters, G Shen, G. David Price, GS Robertson, JC Castle, John P. Brodholt, M Matsui, M O'Keeffe, O Sugino, P Hohenberg, R Car, S Nosé, S-i Karato, SE Kesson, W Kohn, Y Wang   +29 more
core   +1 more source

Horizontal mantle flow controls subduction dynamics [PDF]

, 2017
It is generally accepted that subduction is driven by downgoing-plate negative buoyancy. Yet plate age –the main control on buoyancy– exhibits little correlation with most of the present-day subduction velocities and slab dips. “West”-directed subduction
Dal Zilio, Luca, Doglioni, Carlo, Ficini, Eleonora, Gerya, Taras V.   +3 more
core   +1 more source

Noble Gases in Mantle Plumes

Science, 2001
Trieloff et al . ([1][1]) provided neon isotope data to argue that mantle neon originates as a trapped component in meteorites rather than having a pristine solar composition. That finding, if true, has important consequences for understanding the mechanism of volatile input into the mantle ...
Ballentine, C, Porcelli, D, Wieler, R
openaire   +2 more sources

Microspherules Formed by Lightning Strikes

Meteoritics &Planetary Science, EarlyView.
Abstract Natural microspherules are formed by high‐temperature processes and are present throughout the geologic record to the present day. We report the discovery of large numbers of microspherules recovered from a rock pavement in the Pilbara region, Western Australia.
M. R. Boyd, M. J. Genge, A. G. Tomkins
wiley   +1 more source

Ocean rises are products of variable mantle composition, temperature and focused melting [PDF]

, 2014
Author Posting. © The Author(s), 2014. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in Nature Geoscience 8 (2015): 68-
Dick, Henry J. B., Zhou, Huaiyang
core   +1 more source

Polymict melt‐bearing breccia dikes in the Morokweng impact structure formed by slip‐induced mechanical mixing of pseudotachylite and cataclasite along large‐displacement impact faults

Meteoritics &Planetary Science, EarlyView.
Abstract A core drilled through shocked and faulted Archean granitoid gneisses and dolerites in the eroded peak ring of the 70–80 km diameter Morokweng impact structure intersects multiple centimeter‐ to meter‐wide clastic‐matrix breccias containing a polymict clast population of lithic and mineral clasts and altered, millimeter‐ to centimeter ‐size ...
Roger L. Gibson, S'lindile S. Wela, Leonidas C. Vonopartis, Marco A. G. Andreoli   +3 more
wiley   +1 more source