Results 41 to 50 of about 690,278 (261)

Olivine-chrome-spinel equilibrium in chromitites and ultramafites of Rai-Iz massif, Polar Urals

Литосфера, 2016
Olivine and chrome-spinel compositions from chromitites and ore-bearing metamorphosed ultramafic rocks of Rai-Iz massif were compared. It was established that olivine and spinel ferruginosity are directly proportional and increase monotonically from ...
P. B. Shirjaev, N. V. Vakhrusheva
doaj   +2 more sources

Thermal and Transport Properties of Mafic and Ultramafic Rocks of Oman Ophiolite

Sultan Qaboos University Journal for Science, 2016
Thermal and other physical properties of rocks and minerals are of considerable significance for deriving mineralogical and compositional models of the Earth's mantle.
Sayyadul Arafin, Ram N. Singh
doaj   +1 more source

Peixe Zircon as a Quality Control Reference Material in U‐Pb Geochronology by LA‐ICP‐MS

Geostandards and Geoanalytical Research, EarlyView.
Key Points Peixe#0 zircon was characterised for U‐Pb geochronology using CA‐ID‐TIMS, SIMS and a long‐term LA‐ICP‐MS data set. The consistent results establish Peixe#0 as a reference material for U‐Pb quality control. Trace element heterogeneity requires careful, CL‐guided spot selection.
Margareth Sugano Navarro, Erica Martini Tonetto, Elson P. Oliveira, Mauricio Ibañez‐Mejia, Cristina Talavera, Neal J. McNaughton, Jacinta Enzweiler, Michael Wiedenbeck   +7 more
wiley   +1 more source

New Magnetite Reference Material for SIMS δ18O Measurements and a Study of Precision and Accuracy Due to Crystal Orientation Effects

Geostandards and Geoanalytical Research, EarlyView.
Key Points A new magnetite reference material (PF21mt) is available for δ18O measurements by SIMS. Reproducibility of measurement results in two laboratories suggest orientation bias of ±2‰ (2s) at 20 keV. Repeatability improves to ±1‰ (2s) when using a 13 keV protocol, suggesting reduced orientation bias. In situ isotope ratio measurements provide the
Michelle Ulrich, Daniela Rubatto, Maria Rosa Scicchitano, Benita Putlitz, Thomas Bovay   +4 more
wiley   +1 more source

Garnet–Clinopyroxene Double‐Layered Coronae in a Metagabbronorite From the High‐Grade Metamorphic Gföhl Unit, Moldanubian Zone

Journal of Metamorphic Geology, EarlyView.
ABSTRACT This study investigates garnet–clinopyroxene double‐layered coronae in a metagabbronorite from the high‐grade metamorphic Gföhl Unit (Bohemian Massif). The coronae formed at the interfaces between relic magmatic orthopyroxene, still preserved in the cores of the coronae, and the plagioclase‐rich rock matrix.
Rene Asenbaum, Tereza Nemeškalová, Martin Racek, Vojtěch Janoušek, Julian Portenkirchner, Rainer Abart   +5 more
wiley   +1 more source

Petrographic Analysis of Mafic and Ultramafic Rocks in Northern Thailand: Implications for CO₂ Mineralization and Enhanced Rock Weathering Approach

Geosciences
Mafic and ultramafic rocks have become a promising approach for atmospheric carbon dioxide (CO2) reduction, as they are major sources of CO2-reactive minerals, i.e., olivine, pyroxene, plagioclase, and serpentine.
Tadsuda Taksavasu
doaj   +1 more source

Multi-stage serpentinization of ultramafic rocks in the Manlay Ophiolite, southern Mongolia

Mongolian Geoscientist, 2021
Serpentinization of ultramafic rocks in ophiolites is key to understanding the global cycle of elements and changes in the physical properties of lithospheric mantle.
Amarbayar Nomuulin, Noriyoshi Tsuchiya, Otgonbayar Dandar, Atsushi Okamoto, Masaoki Uno, Undarmaa Batsaikhan, Jiajie Wang   +6 more
doaj   +1 more source

SHRIMP ion probe zircon geochronology and Sr and Nd isotope geochemistry for southern Longwood Range and Bluff Peninsula intrusive rocks of Southland, New Zealand [PDF]

, 2006
Permian–Jurassic ultramafic to felsic intrusive complexes at Bluff Peninsula and in the southern Longwood Range along the Southland coast represent a series of intraoceanic magmatic arcs with ages spanning a time interval of 110 m.y.
Aronson JL, Bignall G, Bryan WB, Challis GA, Corfu F, Devereux I, Ewart A, Graham IJ, Hanchar JM, Kroenke LW, Mossman DJ, Mutch AR, Mutch AR, Rombouts M, Wadsworth CA, Williams JG   +15 more
core   +2 more sources

Petrography and mineral chemistry of Northeast Africa 053—A remnant of Martian crystal mush

Meteoritics &Planetary Science, EarlyView.
Abstract In Earth's igneous systems, crystal mushes, crystal‐rich frameworks permeated by silicate melt, represent a common and fundamental stage in the evolution of magma bodies. However, whether crystal mushes occur within Martian igneous systems and play a comparable role is unknown. Here, we present a comprehensive petrography and mineral chemistry
Xhonatan Shehaj, Eleonora Ammannito, Giovanni Pratesi   +2 more
wiley   +1 more source

Platinum group element mineralization at Musongati (Burundi) : concentration and Pd-Rh distribution in pentlandite [PDF]

, 2017
The mafic-ultramafic intrusions of the Karagwe-Ankole belt in Burundi are considered as a new potential source for platinum group elements (PGE). The intrusions have mainly been studied for their PGE potential with regard to PGE concentration, but the ...
Dewaele, Stijn, Muchez, Philippe, Paredis, Bram   +2 more
core   +1 more source