Results 71 to 80 of about 2,177 (171)

Late Pleistocene Volcanic Rocks From Tengchong Volcanic Field at SE Tibetan Plateau: Constraints on Petrogenesis and Mantle and Crustal Processes

Geological Journal, EarlyView.
Early zircon saturation and crystallisation occur in mafic (52–54 wt.% SiO2) lavas at Tengchong volcanic field. These early formed zircons with high δ18O (6.6‰–7.9‰) indicates mantle enrichment by subducted supracrustal materials. ABSTRACT Late Pleistocene (< 0.2 Ma) mafic and evolved volcanic rocks occur in northern Tengchong Volcanic Field, SE ...
Lizhu Wang, Haibo Zou
wiley   +1 more source

Generalized Stacking Fault Energies of Aluminum Alloys–Density Functional Theory Calculations

Metals, 2018
Generalized stacking fault energies of aluminum alloys were calculated using density functional theory. Stacking fault energy of aluminum alloys was correlated with the d-electrons number of transition metal alloying elements. The tendency to twinning is
Marek Muzyk, Zbigniew Pakieła, Krzysztof J. Kurzydłowski   +2 more
doaj   +1 more source

A Reassessment of Petrochemistry of ~1.2 Ga Tonalitic Rocks of the Northern Tugela Terrane, Natal Metamorphic Belt, South Africa: Further Constraints on the Evolution of This Belt

Geological Journal, EarlyView.
Our petrochemical studies on ~1.2 Ga granitoids of the Natal Metamorphic Belt, South Africa, do not suggest any property similar to Phanerozoic‐style subduction‐related granitoids. Plot of Kotongweni Tonalite in Y versus Sr diagram (after Moyen 2011), note that most samples have Sr/Y < 50.
Palesa Leuta, Saumitra Misra, Thembiso O. Basupi   +2 more
wiley   +1 more source

Geochemical Features of the Weathered Materials Developed on Gabbro in a Semi-Arid Zone, Northern Cameroon

Geosciences, 2017
Investigation on the mobilization and the redistribution of major, trace and rare-earth elements (REE) was performed along a soil profile developed on gabbro in the semi-arid zone (Northern Cameroon), using mineralogical and geochemical analyses.
Désiré Tsozué, Paul-Désiré Ndjigui
doaj   +1 more source

Apatite in Carbonatite Preserving Primary Magmatic, Post‐Magmatic Overgrowth, and Post India‐Asia Collision‐Related Hydrothermal Alteration: Evidenced From U–Pb Isotope and Trace Element Geochemistry

Geological Journal, EarlyView.
U–Pb isotope and trace element geochemistry of apatite from carbonatites of Peshawar Plain Alkaline Igneous Province, western Himalaya shows Permo‐Carboniferous magmatism, an additional magmatic pulse during Cretaceous, and post‐magmatic hydrothermal/metasomatism during Oligocene. ABSTRACT U–Pb isotope and trace element geochemistry of apatite combined
Mehboob ur Rashid, Hafiz U. Rehman, Hao‐Yang Lee, Sun‐Lin Chung, Kaushik Das, Kazumasa Aoki, Muhammad Jawad Zeb, Nasir Ahmad, Muhammad Hussain, Hiroshi Yamamoto   +9 more
wiley   +1 more source

Heterogeneous Exhumation Mechanisms in Neoproterozoic Collisional Metamorphism: P–T Constraints From Pelotas and Punta del Este Terranes, Southern Brazil and Uruguay

Geological Journal, EarlyView.
Petrography, thermobarometry, and pseudosection modelling reveal peak metamorphic conditions of 3–7.5 kbar and 520°C–800°C in Tonian‐Cryogenian orthogneisses of the Dom Feliciano Belt. Metamorphic field gradients of 27°C/km–39°C/km and variable exhumation mechanisms support correlation of these units as remnants of a Himalayan‐type Piratini Orogeny ...
Thaiane Niederauer‐Santos, Carla Cristine Porcher, Daniel Triboli Vieira, Edinei Koester, Diego Jaldín, Karina Luengo, Luisa Caon   +6 more
wiley   +1 more source

Mineralogy and mineral chemistry of rare-metal pegmatites at Abu Rusheid granitic gneisses, South Eastern Desert, Egypt

Geologija, 2011
The Abu Rushied area, situated in the South Eastern Desert of Egypt is a distinctive occurrence of economically important rare-metal mineralization where the host rocks are represented by granitic gneisses.
Mohamed Fahmy Raslan, Mohamed A. Ali
doaj  

Corrosion Behavior of Commercial FeCrAl and TiAl Alloys in Molten Pb With 2E‐7 wt% Oxygen at 600°C and 700°C

Materials and Corrosion, EarlyView.
Excellent corrosion resistance of commercial Al‐containing materials is shown for exposures to liquid lead (Pb) at 600°C. However, oxide scale failure occurs at 700°C. The formed oxide scales and their failure mechanisms are explored. ABSTRACT Liquid lead (Pb) is an attractive heat transfer fluid for advanced thermal energy storage (TES) systems.
Renate Fetzer, Anisa Purwitasari, Annette Heinzel, Alfons Weisenburger, Georg Müller   +4 more
wiley   +1 more source

Glass from Teniky (Madagascar): Geochemical Evidence for Multiple Production Systems and Long‐Distance Exchange in the Mediaeval Indian Ocean

Archaeometry, EarlyView.
ABSTRACT The inland rock‐cut site of Teniky, located in the Isalo massif of southern Madagascar, represents an exceptional archaeological context recently dated to the 11th–12th centuries ad, corresponding to the early phases of settlement on the island.
Jean Rodier, Bernard Gratuze, Vincent Serneels   +2 more
wiley   +1 more source

(Ultra)high‐Pressure Metamorphism in Sedimentary Versus Basaltic Rocks: Insights From a Variscan Mélange in the South Carpathians

Journal of Metamorphic Geology, EarlyView.
ABSTRACT Reconstructing the pressure–temperature–time (P–T–t) evolution of (ultra)high‐pressure rocks is essential for constraining subduction and collisional dynamics. Subduction zones are often investigated using basic eclogites, whereas nonbasic high‐pressure rocks remain comparatively understudied, potentially hindering a comprehensive ...
Otavio S. G. Silva, Bruno V. Ribeiro, Gavril Săbău, Fabricio Caxito, Paulo A. de Paiva‐Silva, Pierre Lanari, George Luvizotto, Mahyra Tedeschi   +7 more
wiley   +1 more source