Results 31 to 40 of about 811 (185)

First report of an Ediacarian basement in the Western Alps: the Serre Chevalier crystalline unit (Briançonnais domain, France)

BSGF - Earth Sciences Bulletin, 2023
We report new LA-ICP-MS U-Pb zircon ages of varied crystalline rocks occurring in the Serre Chevalier crystalline terrain, an allochtonous basement unit located at the top of the Briançonnais nappes stack ∼5 km west of Briançon city.
Thiéblemont Denis, Jacob Jean-Baptiste, Lach Philippe, Guerrot Catherine, Leguérinel Mathieu   +4 more
doaj   +1 more source

Petrography and geochemistry of the Pedra Dourada Granulite, southeastern Minas Gerais, Brazil

REM: International Engineering Journal
The Pedra Dourada Granulite (PDG) occurs at the southeastern portion of the Araçuaí Belt, north of the town of Ponte Nova. It comprises bodies up to 45 km2 inserted into amphibolite-facies gneisses of the Mantiqueira Complex. Motivated by the discrepancy
Kassia de Souza Medeiros Marinho, Hanna Jordt-Evangelista, Marcelo de Souza Marinho   +2 more
doaj   +1 more source

Geochemical constraints on provenance and source area weathering of metasedimentary rocks from the Paleoproterozoic (~2.1 Ga) Wa-Lawra Belt, southeastern margin of the West African Craton

Geodinamica Acta, 2019
The Wa-Lawra Belt which is situated in the northern part of Ghana consists of Paleoproterozoic Birimian fine metasedimentary rocks metamorphosed to greenschist facies, particularly, in the western part.
Daniel K. Asiedu, Magdalene Agoe, Prince O. Amponsah, Prosper M. Nude, Chris Y. Anani   +4 more
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

Timing of Metamorphism and Deformation in the Neoarchean Quetico Metasedimentary Belt, Superior Craton, Constrained by Garnet Trace‐Element Mapping and Lu–Hf Geochronology

Journal of Metamorphic Geology, EarlyView.
ABSTRACT The Quetico subprovince of the Superior Province is among the largest metasedimentary belts globally and provides evidence of tectonic processes at play during the final stages of Archean cratonization. Although previous studies have shown that deformation and metamorphism of the 2.7‐Ga turbiditic protolith resulted in regional subvertical ...
Adrian G. Rehm, Antoine Godet, Doug Tinkham, Carl Guilmette, Matthijs A. Smit   +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

LITHOSTRUCTURAL RELATIONSHIPS AND PETROGENETIC AFFINITIES OF THE BASEMENT COMPLEX ROCKS AROUND OKPELLA, NIGERIA [PDF]

Earth Science Malaysia, 2018
Okpella area is the eastern extension of the Igarra Schist Belt, Southwestern Nigerian Basement Complex. The area comprises granite gneiss, metasedimentary rocks and Pan-African intrusives.
Ogunyele, A. C., Obaje, S. O.,, Akingboye, A. S.   +2 more
doaj  

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

The Vazante and Canastra groups revisited: Sm-Nd and Sr isotopes - evidence for contribution from Tonian intraplate magmatism during passive margin development along the SW São Francisco margin, Brazil

Brazilian Journal of Geology, 2019
Combined Sm-Nd isotope studies and U-Pb ages of detrital zircons have shown significant differences between the provenance patterns of Neoproterozoic metasedimentary successions in the Southern Brasília belt.
Manuela de Oliveira Carvalho, Claudio de Morisson Valeriano, Carla Cristine Aguiar Neto, Gustavo Diniz Oliveira, Monica Heilbron   +4 more
doaj   +1 more source

On reasons of specific composition of the Keivy domain rocks (the Kola Peninsula) [PDF]

Vestnik MGTU, 2017
The Keivy domain differs from the other structures of the Kola region by the specific composition of the metamorphic complexes, the presence of the oldest for the region alkaline granites and gabbroanorthosites associated with them as well as by the ...
Kozlov N. E., Fomina E. N., Martynov E. V., Sorokhtin N. O., Marchuk T. S.   +4 more
doaj   +1 more source