Results 31 to 40 of about 761 (228)

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

MECHANISMS OF MANTLE‐CRUST INTERACTION AT DEEP LEVELS OF COLLISION OROGENS (CASE OF THE OLKHON REGION, WEST PRIBAIKALIE)

Геодинамика и тектонофизика, 2017
In the Chernorud granulite zone in the Olkhon region of West Pribaikalie, we studied gabbro‐pyroxenites composing tectonic plates (Chernorud, Tonta) and synmetamorphic intrusive bodies (Ulan‐Khargana), as well as nu‐ merous disintegrated boudins and ...
A. G. Vladimirov, A. S. Mekhonoshin, S. V. Khromykh, E. I. Mikheev, A. V. Travin, N. I. Volkova, T. B. Kolotilina, Yu. A. Davydenko, E. V. Borodina, V. V. Khlestov   +9 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

Igneous and Metamorphic Petrology

Eos, Transactions American Geophysical Union, 1983
So many new and exciting topics in petrology have appeared over the last several years that it has become difficult to find a text that deals adequately with fundamentals as well as current topics; the present book may be one of the better texts in its field today because it achieves this combination with clarity and appropriate emphasis.
openaire   +1 more source

Evolving Subduction Zone Thermal Structure Drives Extensive Forearc Mantle Wedge Hydration

AGU Advances
Hydration of the subduction zone forearc mantle wedge influences the downdip distribution of seismicity, the availability of fluids for arc magmatism, and Earth's long term water cycle.
G. S. Epstein, C. B. Condit, R. K. Stoner, A. F. Holt, V. E. Guevara   +4 more
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

The composition of metapelitic biotite, white mica, and chlorite: a review with implications for solid-solution models [PDF]

European Journal of Mineralogy
Biotite, white mica, and chlorite record petrological processes and pressure–temperature conditions. Unfortunately, their crystal chemistry is complicated and thermodynamic modelling of their phase relations is hindered by this complexity.
B. Dubacq, J. B. Forshaw
doaj   +1 more source

A talus rock glacier in Nantlle Valley, North Wales

Journal of Quaternary Science, EarlyView.
ABSTRACT Landforms comprising mixtures of fine and coarse sediment and deposited during late glacial times are ubiquitous in the British mountains. In many cases, their interpretation has often proved contentious; as a result, the non‐generic term discrete debris accumulations (DDA) has been used to describe them and, over the last 50 years, some have ...
Stephan Harrison, Ed Anderson
wiley   +1 more source

Controlling factors of coal petrology, coal quality, and coal type characteristics and classification of genesis types of special coal in Ningxia

Meitan kexue jishu
Promoting the transition of coal resources from fuel to both fuel and raw material, and achieving clean and efficient utilization of coal are crucial approaches to addressing energy, resource, and environmental challenges in the 21st century.
Yingchun WEI, Xin WANG, Xiaoyan JI, Daiyong CAO, Yongping LIANG, Xin LI, Jingqi LI, Wenhao ZHU   +7 more
doaj   +1 more source