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Sr and Nd isotope composition of the metamorphic, sedimentary and ultramafic xenoliths of Lanzarote (Canary Islands): Implications for magma sources
(ELSEVIER SCIENCE BV, 2010)
The lavas produced by the Timanfaya eruption of 1730-1736 (Lanzarote, Canary Islands) contain a great many sedimentary and metamorphic (metasedimentary), and mafic and ultramafic plutonic xenoliths. Among the metamorphosed ...
Andean subduction-related mantle xenoliths: Isotopic evidence of Sr-Nd decoupling during metasomatism
(ELSEVIER SCIENCE BV, 2005-06)
Sr-Nd isotopic analyses on some mantle xenolith samples from the Northern, Southern and Austral Andean volcanic zones exhibit radiogenic Sr enrichment without dramatic changing of the Nd isotopic composition. This anomalous ...
A spectrum of disequilibrium melting preserved in lava-hosted, partially melted crustal xenoliths from theWudalianchi volcanic field, NE China
(Elsevier, 2015)
Disequilibrium melting has been established as a common process occurring during crustal anatexis and thus demonstrates that crustal assimilation is not a closed system. Observations of extreme compositional heterogeneity ...
Petrology and geochemistry of the back-arc lithospheric mantle beneath eastern Payunia (La Pampa, Argentina): evidence from Agua Poca peridotite xenoliths
(Geochemical Society of Japan, 2013-04)
This paper presents the results of new petrochemical studies carried out on mantle xenoliths hosted in Pleistocene basaltic rocks from the Agua Poca volcano in central-western Argentina. Mantle xenoliths studied are shown ...
Major- and trace-element compositions of indicator minerals that occur as macro- and megacrysts, and of xenoliths, from kimberlites in Northeastern Angola
(MDPI, 2012-10)
In this study, we compare the major- and trace-element compositions of olivine, garnet, and clinopyroxene that occur as single crystals (142 grains), with those derived from xenoliths (51 samples) from six kimberlites in ...
The upper mantle beneath Patagonia, Argentina, documented by xenoliths from alkali basalts
(Pergamon-Elsevier Science Ltd, 2005-01)
Mantle xenoliths in alkali basaltic lavas (with ocean-island basalt chemical signatures) and cinder cones occur in several areas of Patagonia. A representative suite of mantle xenoliths was collected in the region between ...
Equivocal carbonatite markers in the mantle xenoliths of the patagonia backarc: The Gobernador Gregores case (Santa Cruz Province, Argentina)
(Springer, 2004-08)
Amphibole ± phlogopite ± apatite-bearing mantle xenoliths at Gobernador Gregores display modal, bulk-rock and phase geochemical characteristics held as indicators of carbonatitic metasomatism. However, part of these xenoliths ...
The origin of Patagonia revealed by Re-Os systematics of mantle xenoliths
(Elsevier, 2017-06)
We present mineral chemistry and whole rock major, trace, and platinum group element (PGE) concentrations, and Re-Os isotope data for eighteen mantle xenoliths carried to the surface of southern Patagonia (45 degrees-52 ...
Origin of the DUPAL anomaly in mantle xenoliths of Patagonia (Argentina) and geodynamic consequences
(Elsevier Science, 2016-04)
The sub-continental lithospheric mantle of South America has been known for some time to carry the DUPAL isotope anomaly as seen in volcanics from the Paraná volcanic province. However, this has not allowed discriminating ...