Results 41 to 50 of about 18,330 (214)

Granitoides e séries magmáticas: o estudo contextualizado dos granitoides

Pesquisas em Geociências, 2016
A relação que muitas rochas graníticas possuem com magmas menos diferenciados provenientes do manto tem sido subestimada nas últimas décadas, perdendo-se assim uma poderosa ferramenta científica para investigação de ambientes geotectônicos antigos e da própria evolução do sistema manto-crosta. Propõem-se neste trabalho que os magmas graníticos passem a
openaire   +3 more sources

The making of pure quartzose sand in continental interiors: Paraná River (Brazil and Argentina)

Sedimentology, EarlyView.
ABSTRACT As part of a comprehensive project on sedimentary processes in South America, this study focuses on sediment generation in the intracratonic Paraná Basin and monitors the evolution of sand composition along the Paraná River from central Brazil to the Río de la Plata estuary in Argentina.
Eduardo Garzanti, Marta Barbarano, Mara Limonta, Guido Pastore, Pieter Vermeesch, Giovanni Vezzoli   +5 more
wiley   +1 more source

Petrogenesis and geological significance of the Mesozoic granitoids in the Mangzhang-Jiucheng area, Tengchong terrane, Yunnan province: evidence from petrology, geochemistry and zircon U-Pb geochronology

Frontiers in Earth Science
The Mangzhang-Jiucheng granitoids of the Tengchong Terrane offers critical insights into the Mesozoic tectono-magmatic evolution of the eastern Tethyan Tectonic Domain.
Wei Liu, Wei Liu, Jinglong Wu, Yuelei Ruan, Chen Gong, Yan Shang, Geng Chen, Yuan Liu, Jialing Wu, Xiaojun Li, Xiaofeng Wang, Xu Kong, Xiong Mo   +12 more
doaj   +1 more source

Near‐Synchronous Cambrian Evolution of the Transbrasiliano‐Kandi‐4°50′ Shear Zone in South America and Africa

Terra Nova, EarlyView.
ABSTRACT The Transbrasiliano‐Kandi‐4°50′ (TK4) shear zone in western Gondwana crosscuts South America and NW Africa for at least 6000 km. Despite its impressive size, the timing of the main episode of dextral ductile shearing is uncertain. We present detailed in situ multi‐mineral geochronology of mylonites from both Brazil and Algeria supporting that ...
F. A. Caxito, B. V. Ribeiro, F. Alkmim, A. Deramchi, C. L. Kirkland   +4 more
wiley   +1 more source

Late Mesozoic adakite granites of the southern frame of the eastern flank of the Mongol-Okhotsk orogenic belt: material composition and geodynamic conditions of formation

Геодинамика и тектонофизика, 2020
Granitoids of the Magdagachi complex were studied using new and published petrochemical, geochemical and isotopic (Sm-Nd, Rb-Sr) data. Granitoid samples were taken from the southern frame of the eastern flank of the Mongol-Okhotsk orogenic belt (MOOB ...
I. M. Derbeko, A. V. Chugaev
doaj   +1 more source

Subcritical Cracking Associated With Subgrain Rotation Recrystallisation in Quartz Inferred From Cathodoluminescence Study

Terra Nova, EarlyView.
ABSTRACT We employed cathodoluminescence (CL) to study deformed quartz phenocrysts from the Cretaceous granite porphyry in SW Japan and observed fracture‐like planar structures appearing as CL‐dark bands. These CL‐dark bands were aligned with low‐angle grain boundaries formed by subgrain rotation recrystallisation.
Takuro Yoshioka, Takamoto Okudaira, Hideo Takagi   +2 more
wiley   +1 more source

The Archean Granitoid-Paleoproterozoic Unconformity: Superimposition of Alteration Events in Archean Granitoids, Gabon

Procedia Earth and Planetary Science, 2013
AbstractThe Archean granitoids of the South Gabon, dated from 3.0-to-2.5 Ga, were examined along the Archean-Proterozoic unconformity. The petrography was based on mineralogical identification using electron microscopy, X-ray diffraction, and the electron microprobe.
Idalina, Mouélé Moubiya, Dudoignon, Patrick, El Albani, Abderrazak, Martin, Hervé, Paquette, Jean-Louis, Cuney, Michel, Gauthier-Lafaye, François   +6 more
openaire   +3 more sources

New data on geochemical features, fluid mode, age and potential ore content of granitoids of Isherim anticlinorium (North Ural)

Литосфера, 2018
Granitoids of Ishirim anticlinorium which is one of the major Precambrian structures of the North Urals, are poorly studied by modern geochemical and isotope-geochronological methods that led to the existence of different points of view on formation ...
Georg A. Petrov, Vladimir V. Holodnov, Yurii L. Ronkin   +2 more
doaj   +1 more source

Pre-Variscan granitoids with adakitic signature at west Getic basement of the South Carpathians (Romania): constraints on genesis and timing based on whole-rock and zircon geochemistry

Geologica Acta, 2021
Research on two strata-like intrusions from Slatina-Timiş (STG) and Buchin (BG) at West Getic Domain of the South Carpathians (Semenic Mountains) identified granitoids with adakitic signature in a continental collision environment. Whole-rock geochemical
Anca Dobrescu
doaj   +1 more source

Evolution of the Transantarctic Basin (Southern Gondwana): Insights From Quantitative Sandstone Petrography

New Zealand Journal of Geology and Geophysics, Volume 69, Issue 1, March 2026.
The deposition of the sandstone sedimentary succession of the Beacon Supergroup lasted more than 200 Myr (Devonian to Early Jurassic) in Victoria Land and nearby territories in the so‐called Transantarctic Basin, recording crucial events in the history of the Earth.
Luca Zurli, Marco Fioraso, Matteo Perotti, Andrea Di Giulio, Valerio Olivetti, Samuele Pezzoli, Valentina Corti, Gianluca Cornamusini   +7 more
wiley   +1 more source