Results 51 to 60 of about 3,940 (219)

Geochemical and Geological Investigation of Skarn‐Type Pb–Zn Mineralization in Hastanetepe (Balya‐Balıkesir, Türkiye): An Approach Based on Fluid Inclusions, Sulphur Isotopes and Geochemical Data

Geological Journal, EarlyView.
Integrated petrographic, mineralogical and geochemical data from the Hastanetepe Pb–Zn deposit (Balya, Türkiye) reveal multi‐stage hydrothermal alteration and a magmatic sulphur source. Fluid inclusion and sulphur isotope results indicate a complex fluid evolution responsible for skarn‐type Pb–Zn mineralization along limestone–dacite contacts ...
Esra Ünal‐Çakır
wiley   +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

Imbrication and Erosional Tectonics Recorded by Garnets in the Sikkim Himalayas

Geosciences, 2022
The Sikkim region of the Himalayas (NE India) may form an important microplate between Nepal and Bhutan. Here we report high-resolution pressure-temperature (P-T) paths taken from garnet-bearing rocks across the northern and eastern portion of the region’
Elizabeth J. Catlos, Chandra S. Dubey, Thomas M. Etzel   +2 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

Cooling history of the eastern Svecokarelides: whole-rock and mica Rb-Sr and hornblende K-Ar ages in the areas of Pihtipudas-Iisalmi and Joroinen-Sulkava, Finland [PDF]

Bulletin of the Geological Society of Finland, 1990
Rb-Sr age determination on mica and whole-rock samples and K-Ar age determination on hornblendes were carried out to get information on the time of metamorphism and early cooling in two Proterozic areas of the Finnish Svecokarelides.
U. Haudenschild
doaj   +1 more source

Spatio-Temporal Evolution of Intermediate-Depth Seismicity Beneath the Himalayas: Implications for Metamorphism and Tectonics

Frontiers in Earth Science, 2021
Intermediate-depth earthquakes (>40 km) have been observed beneath the central Himalayas over decades, with little known about their nature and characteristics.
Konstantinos Michailos, N. Seth Carpenter, N. Seth Carpenter, György Hetényi   +3 more
doaj   +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

Metamorphism and Metamorphic Rocks

, 2013
In the previous chapters, we learned about igneous and sedimentary rocks. This chapter presents some general concepts concerned with the process of metamorphism and the formation of metamorphic rocks. How pressure, temperature, and fluids control metamorphic processes and resulting metamorphic changes are discussed.
openaire   +1 more source

Neural Networks and Multivariate Analysis Based on Geochemical Data to Determine Stone Provenance From Ancient Calabrian Quarries (Southern Italy)

Archaeometry, EarlyView.
ABSTRACT This study shows an innovative approach to determine the origin of some Calabrian rocks quarried used in ancient times. Twenty‐five quarries, distributed in all the Calabrian provinces (Southern Italy), were studied and sampled. Ten samples were taken from each quarry, for a total of 250 samples.
Domenico Miriello, Stefano Columbu, Raffaella De Luca, Marco Lezzerini, Mirco Taranto, Fabrizio Antonelli   +5 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