Results 21 to 30 of about 530 (129)

Thermo‐Compositional Structure of the South American Platform Lithosphere: Evidence of Stability, Modification, and Erosion

Geochemistry, Geophysics, Geosystems, 2022
Constraints on the structure of cratonic lithosphere are essential to improve our understanding of craton formation, evolution and long‐term stability.
Isabella Altoe, Saskia Goes, Marcelo Assumpção   +2 more
doaj   +1 more source

Mineralogical evolution of the northern Bossoroca ophiolite, São Gabriel terrane

Brazilian Journal of Geology, 2020
Mineralogical evolution of ophiolites is significant to understand paleo-oceanic crust and mantle requiring multi-proxy techniques to identify steps in the processes. We studied the Bossoroca ophiolite from the southern Brasiliano Orogen, a prime example
Amanda Juliano Massuda, Léo Afraneo Hartmann, Gláucia Nascimento Queiroga, Marco Paulo de Castro, Carolina Gonçalves Leandro, Jairo Francisco Savian   +5 more
doaj   +1 more source

Ti-Nb Mineralization of Late Carbonatites and Role of Fluids in Its Formation: Petyayan-Vara Rare-Earth Carbonatites (Vuoriyarvi Massif, Russia)

Geosciences, 2018
This article is devoted to the geology of titanium-rich varieties of the Petyayan-Vara rare-earth dolomitic carbonatites in Vuoriyarvi, Northwest Russia. Analogues of these varieties are present in many carbonatite complexes. The aim of this study was to
Evgeniy Kozlov, Ekaterina Fomina, Mikhail Sidorov, Vladimir Shilovskikh   +3 more
doaj   +1 more source

Xenoliths in the alkali basalts of Makhtesh Ramon of Desert Negev (Israel) as indicators of mantle metasomatosis and magma generation

Литосфера, 2016
Xenoliths in the Early Cretaceous alkali basalts of Makhtesh Ramon basin (southern Israel) are represented by essentially olivine rocks: dunite (usually including clinopyroxen) - 5% of the total amount, lherzolite - 21%, wehrlite - 28%, clinopyroxenite -
G. B. Fershtater, Z. A. Yudalevich, V. V. Khiller   +2 more
doaj   +2 more sources

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

Evaluating maturity of organic matter in hydrated C1 and CM‐like clasts and a dehydrated clast within a polymict eucrite and a howardite

Meteoritics &Planetary Science, EarlyView.
Abstract Volatile‐rich xenolithic clasts in different types of brecciated meteorites represent unique pristine solar system material. This study investigates the maturity and thermal history of organic matter using Raman spectroscopy and aqueous alteration effects using infrared spectroscopy in the matrix of 15 volatile‐rich clasts (C1 and CM‐like ...
Swarna Prava Das, Alessandro Maturilli, Aurélie Van den Neucker, Markus Patzek, Dipak Kumar Panda, Gopal K. Pradhan, Guneshwar Thangjam, Surya Snata Rout   +7 more
wiley   +1 more source

Nature, origin, and phosphorylation potential of the phosphorus/sulfur‐bearing nanoscale multiphasic assemblages in the CM chondrites Murchison and Murray

Meteoritics &Planetary Science, EarlyView.
Abstract Carbonaceous chondrites contain phosphorus, whose speciation and thus history remain to be investigated. Phosphorus/sulfur‐bearing assemblages have been reported in carbonaceous CM chondrites, but there is no consensus about their exact compositions and origins.
Valentine Megevand, Sylvain Bernard, Corentin Le Guillou, Roberto Conconi, François Guyot   +4 more
wiley   +1 more source

The first discovery of a shocked, metasomatised CV3 chondrule‐fragment in a (Al,Cu)‐bearing micrometeorite

Meteoritics &Planetary Science, EarlyView.
Abstract We report the discovery of the second (Al,Cu)‐alloy–bearing micrometeorite, FB‐A2, recovered from Mount Gariglione (southern Italy), representing the sixth such occurrence worldwide. Although chondritic in nature, FB‐A2 differs markedly from previously described microspherules.
Giovanna Agrosì, Paola Manzari, Daniela Mele, Johan Villeneuve, Tiziano Catelani, Mattew J. Genge, Luca Bindi   +6 more
wiley   +1 more source

Metasomatites of medium and mafic composition from Nyaschevo massif (Ilmeny Mauntains, South Urals)

Литосфера, 2015
The results of the study of mediosiliceous and mafic metasomatites located in ultramafic and mafic rocks Nyaschevo massif presents in the paper. The texthural and structural features of these rocks allow to attribute them to tectonites - protomylonites and
E. V. Medvedeva, A. B. Nemov, V. A. Kotlyarov   +2 more
doaj   +2 more sources

Thallium Isotopes Reveal Brine Activity During Carbonatite Magmatism

Geochemistry, Geophysics, Geosystems, 2021
Carbonatite volcanism remains poorly understood compared to silicic volcanism due to the scarcity of carbonatite volcanoes worldwide and because volcanic H2O and CO2—major components in carbonatite volcanic systems—are not well preserved in the rock ...
Forrest Horton, Sune Nielsen, Yunchao Shu, Alan Gagnon, Jerzy Blusztajn   +4 more
doaj   +1 more source