Results 21 to 30 of about 1,482 (183)
Anais da Academia Brasileira de Ciências, 2014 Subduction zone or arc magmas are known to display a characteristic depletion of High Field Strength Elements (HFSE) relative to other similarly incompatible elements, which can be attributed to the presence of the accessory mineral rutile (TiO2) in the ...
GUILHERME MALLMANN +2 more
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Geochemistry, Geophysics, Geosystems, 2023 The behavior of Fe3+ during mantle partial melting strongly influences the oxidation state of the resulting magmas, with implications for the evolution of the atmosphere's oxidation state.
Yves Moussallam +7 more
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Frontiers in Earth Science, 2020 Large volcanic eruptions are frequently triggered by the intrusion of hot primitive magma into a more evolved magma-chamber or -mush zone. During intrusion into the cooler mush zone, the basaltic magma undergoes crystallization, which in turn can release
Stephan Kolzenburg +5 more
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Scientific Reports, 2017 We present the first oxygen fugacity (fO2) profile through the cratonic lithospheric mantle under the Panda kimberlite (Ekati Diamond Mine) in the Lac de Gras kimberlite field, central Slave Craton, northern Canada.
G. M. Yaxley +4 more
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Journal of Economic Geology, 2017 Introduction Mineral composition is sensitive to variations in the composition of the magma and can be used to characterize the physical conditions of crystallization such as temperature, pressure, oxygen fugacity and water content.
Fatemeh Sarjoughian
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Upper mantle oxygen fugacity recorded by spinel lherzolites
Nature, 1986 The oxygen fugacities ( ) recorded by rocks from the Earth's upper mantle have been the subject of much recent study and controversy1–7. Discussion has been stimulated by reported differences of several orders of magnitude between measurements made by different methods (Fig.
Mattioli, G, Wood, B
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Mineral chemistry and geothermobarometry of gabbroic dykes of the Garmab Ophiolite sequence (Northeast of Kamyaran) [PDF]
پترولوژی, 2018 The Garmab ophiolite complex, a part of the Ophiolite-Radiolithic zone of Kermanshah, is located in the northeast of Kamyaran. In view of the Iranian geo-structural zones, this complex is situated between the Sanandaj-Sirjan Zone and the Zagros thrust ...
shahryar Mahmoudi +2 more
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Petrography and mineral chemistry of Rosário-16 Kimberlite: an inference of P, T, and fO2 for an ultramafic alkaline assemblage in Southern Brazil [PDF]
Brazilian Journal of GeologyRosário-16 (R-16) is a hypabyssal transitional kimberlite, divided into two volcanic pipes, R-16-A and R-16-B, within the Kimberlite Province of Rosário do Sul (KPRS), southeast of the Paraná Basin (PB), southeast Brazil. The saprolite outcrops, within a
Andrea Brum da Silva +5 more
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Covariation of Slab Tracers, Volatiles, and Oxidation During Subduction Initiation
Geochemistry, Geophysics, Geosystems, 2021 Subduction‐related lavas have higher Fe3+/∑Fe than midocean ridge basalts (MORB). Hypotheses for this offset include imprint from subducting slabs and differentiation in thickened crust.
Maryjo Brounce +5 more
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Oxygen fugacity at the base of the Talkeetna arc, Alaska
Contributions to Mineralogy and Petrology, 2019 The origin of the more oxidized nature of arc magmas as compared to that of mid-ocean ridge basalts (MORB) is debated, considered to be either a feature of their mantle source, or produced during crustal transit and eruption. Fe3+/FeT ratios (Fe3+/[Fe3+ + Fe2+]) in arc volcanic rocks and glasses and thermodynamic oxybarometry on mantle xenoliths from ...
Claire E. Bucholz, Peter B. Kelemen
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