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The Precambrian Taratash complex (Middle Urals) is one of the rare windows into the Palaeoproterozoic and earlier history of the eastern margin of the East European Craton. Monazite from intensively deformed rocks within a major amphibolite-facies shear zone in the Taratash complex has been investigated by means of electron-probe microanalysis and laser-ablation SF-ICP-MS.Metamorphic and magmatic...
We analyzed major and trace elements, Sr and Nd isotopes in ultramafic xenoliths in Miocenic age Hyblean diatremes, along with noble gases of CO 2 -rich fluid inclusions hosted in the same products. The xenoliths consist of peridotites and pyroxenites, which are considered to be derived from the upper mantle. Although the mineral assemblage of peridotites and their whole-rock abundance of...
The Late Cretaceous–Tertiary accretionary prism in Eastern Turkey includes several ophiolitic megablocks and/or tectonic slivers (Mehmetalan, Mollatopuz and Alabayir) within a mélange complex, mainly comprising harzburgite, dunite and cumulate-textured gabbro. The diabases, which are the main focus of this study, cut across the ophiolites as parallel and variably thick dyke-swarms. Geochemistry of...
The Neoproterozoic Wadi Ranga metavolcanic rocks, South Eastern Desert of Egypt, constitute a slightly metamorphosed bimodal sequence of low-K submarine tholeiitic mafic and felsic volcanic rocks. The mafic volcanic rocks are represented by massive and pillow flows and agglomerates, composed of porphyritic and aphyric basalts and basaltic andesites that are mostly amygdaloidal. The felsic volcanic...
Lithium isotope signatures of whole rock pegmatite samples and mineral separates from the rare element-bearing Little Nahanni Pegmatite Group, NWT, and whole rock samples from nearby granitic intrusions were measured. Correlation of the Li isotopic values from the pegmatite dikes with whole rock trace element geochemistry, mineralogy and primary textural evidence reflect mechanisms of Li isotopic...
We have studied a visibly zoned, thin (<0.5m) lamprophyre sill that crops out in the Catalonian Coastal Ranges (NE Spain). The sill is a camptonite composed of large abundant crystals, mainly of clinopyroxene and amphibole, set in a fine-grained groundmass. The mineral chemistry of the different crystal populations indicates that the large crystals are inherited antecrysts incorporated into the...
Mafic granulite and spinel lherzolite xenoliths from Cenozoic alkaline basalts near Al-Ashkhara, eastern Oman, have been selected for a systematic mineralogical, geochemical and Sr–Nd–Pb isotopic study. This is the only place in E Arabia where samples of both lower crust and upper mantle can be examined. Lower crustal xenoliths consist of two mineralogically and chemically distinct groups: gabbronorite...
A combined approach based on trace elements, radiogenic (Sr–Nd) and stable (O) isotopes allows us to discuss the role of crustal assimilation and mantle metasomatism in Quaternary Ecuadorian magmatism. Magmas emplaced in the Eastern Cordillera have high Sr isotopic ratios and relatively high δ 18 O values, which reflect crustal assimilation (6–13vol.%) of igneous and metamorphic Palaeozoic...
The West Junggar, northwestern China, is located in the southwest of the Central Asian Orogenic Belt (CAOB) and consists of Paleozoic ophiolitic mélanges, arcs and accretionary complexes. The Mayile Mountain ultramafic–mafic mélange in the southern West Junggar is the northeastern part of the Mayile ophiolitic mélange. The Mayile Mountain mélange is represented by a ca. 30km long, 5km wide, north–northeast-striking...
We present new, whole-rock major and trace element chemistry, including rare earth elements (REE), platinum-group elements (PGE), and Re–Os isotope data from the upper mantle peridotites of a Cretaceous Neo-Tethyan ophiolite in the Muğla area in SW Turkey. We also report extensive mineral chemistry data for these peridotites in order to better constrain their petrogenesis and tectonic environment...
The debate on the Mesozoic tectonics of the South China Block (SCB), featuring a broad orogenic belt and a large continental magmatic province, has been rejuvenated in the past years. There are a number of competing tectonic models, each predicting different time, space, and compositional evolutional trends for the Mesozoic igneous rocks, including sporadic basalts. In this paper, we report high precision...
Serpentine muds from South Chamorro Seamount (SCS), drilled during ODP Leg 195 at Site 1200 contain metamafic clasts that experienced blueschist-facies metamorphism (including the critical mineral assemblage pumpellyite – Na-amphibole – epidote). These schists represent fragments from the actual slab–mantle interface at ~27km depth. Their heterogeneous lithology with a metasomatic character indicates...
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