Results 1 to 10 of about 2,995 (201)
Oceanic slab melting and mantle metasomatism [PDF]
Science Progress, 2001 Modern plate tectonic brings down oceanic crust along subduction zones where it either dehydrates or melts. Those hydrous fluids or melts migrate into the overlying mantle wedge trigerring its melting which produces arc magmas and thus additional continental crust. Nowadays, melting seems to be restricted to cases of young (<50 Ma) subducted plates.
Bruno Scaillet, Gaëlle Prouteau
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Field‐Based Evidence for Intra‐Slab High‐Permeability Channel Formation at Eclogite‐Facies Conditions During Subduction [PDF]
Geochemistry, Geophysics, Geosystems, 2021 Fluid release from subducting oceanic lithosphere is a key process for subduction zone geodynamics, from controlling arc volcanism to seismicity and tectonic exhumation.
Francesca Piccoli +4 more
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Evidence of metasomatism in the interior of Vesta [PDF]
Nature Communications, 2020 AbstractDiogenites are a group of meteorites that are derived from the interior of the largest protoplanet Vesta. They provide a unique opportunity to understanding together the internal structure and dynamic evolution of this protoplanet. Northwest Africa (NWA) 8321 was suggested to be an unbrecciated noritic diogenite meteorite, which is confirmed by
Jian-Feng Gao +16 more
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Low‐Degree Melt Metasomatic Origin of Global Upper Mantle Fe Isotope Fractionation
Geophysical Research Letters, 2023 The upper mantle is heterogeneous in Fe isotope compositions, but the origin of the heterogeneity needs understanding. Recent studies on oceanic basalts demonstrate that the upper mantle Fe isotope heterogeneity results from low‐degree melt metasomatism.
Pengyuan Guo +7 more
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Hydrothermal alteration in the lower part of an early Proterozoic greenstone complex at Palovaara, Enontekiö, northwestern Finland [PDF]
Bulletin of the Geological Society of Finland, 1988 The lower part of the early Proterozoic greenstone complex at Palovaara, northwestern Finnish Lapland, comprises a quartzite formation overlain by intermediate and felsic tuffs and tuffites with some lava flows, mostly intermediate in chemical ...
P. Eilu, H. Idman
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Elucidating Pathfinding Elements from the Kubi Gold Mine in Ghana [PDF]
Minerals 11, 912 (2021), 2021 X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray spectroscopy (EDX) are applied to investigate the properties of fine-grained concentrate on artisanal small-scale gold mining samples from the Kubi Gold Project of the Asante Gold Corporation near Dunwka-on-Offin in the Central Region of Ghana.
arxiv +1 more source
Palaeoproterozoic prograde metasomatic-metamorphic overprint zones in Archean tonalitic gneisses, eastern Finland [PDF]
Bulletin of the Geological Society of Finland, 1999 Several occurrences of coarse-grained kyanite rocks are exposed in the Archaean area of eastern Finland in zones trending predominantly northwest-southeast that crosscut all the Archaean structures and, locally, the Palaeoproterozoic metadiabase dykes ...
M. Pajunen, M. Poutiainen
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Sediment-Peridotite Reaction Controls Fore-Arc Metasomatism and Arc Magma Geochemical Signatures
Geosciences, 2021 Subduction of oceanic crust buries an average thickness of 300–500 m of sediment that eventually dehydrates or partially melts. Progressive release of fluid/melt metasomatizes the fore-arc mantle, forming serpentinite at low temperatures and phlogopite ...
Michael W. Förster +6 more
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Mechanisms of metasomatic reactions [PDF]
Mineralogy and Petrology, 2009 Fluid-aided mass transfer and subsequent mineralre-equilibrationarethetwodefiningfeaturesofmetasomatismand must be present in order for metamorphism to occur.Taking into account geological time scales, the amount offluidrequiredneednotbegreat(considerablylessthan0.01%of the total volume) nor even in continuous flow but the fluidmust be chemically ...
Harlov, D., Marschall, H.
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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. +4 more
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