Results 51 to 60 of about 682 (137)

Water in Omphacite and Garnet From Pristine Xenolithic Eclogite: T‐X‐fO2 Controls, Retentivity, and Implications for Electrical Conductivity and Deep H2O Recycling

Geochemistry, Geophysics, Geosystems, 2023
Kimberlite‐borne eclogite xenoliths having Precambrian oceanic crustal protoliths and entrained from ≥100 km depth can retain pristine geochemical features despite extended residence in the cratonic lithospheric mantle, making them valuable archives of ...
Sonja Aulbach, Roland Stalder, Malcolm Massuyeau, Richard A. Stern, Dmitri A. Ionov, Andrey V. Korsakov   +5 more
doaj   +1 more source

Provenance Reassessment of Eocene Turbidites, New Caledonia: Inferences for Obduction Models

Geochemistry, Geophysics, Geosystems
Provenance of pre‐obduction Eocene turbidites from New Caledonia is used to better constrain their geodynamic context and inform debate on subduction polarity.
Dominique Cluzel, France Pattier, Renjie Zhou, Sébastien Meffre, Jonathan C. Aitchison, Pierre Maurizot, Maximilien Mathian, Jean‐Luc Devidal   +7 more
doaj   +1 more source

An evaluation of garnet-clinopyroxene geothermometry in granulites [PDF]

Contributions to Mineralogy and Petrology, 1983
Four new formulations of the garnet-clinopyroxene geothermometer (Ellis and Green 1979; Ganguly 1979; Saxena 1979; Dahl 1980) have been evaluated in the Adirondacks and five other granulite terranes using results from 94 mineral pairs. The Saxena and Ganguly formulations give temperatures that are generally 100–150° C above those constrained by phase ...
Bohlen, S. R., Johnson, C. A., Essene, E J.   +2 more
openaire   +2 more sources

Pyroxenites and Megacrysts From Alkaline Melts of the Calatrava Volcanic Field (Central Spain): Inferences From Trace Element Geochemistry and Sr-Nd Isotope Composition

Frontiers in Earth Science, 2020
Alkaline volcanic rocks from explosive monogenetic centers often carry an unusual cargo of crystals and rock fragments, which may provide valuable constraints on magma source, ascent and eruption.
Carlos Villaseca, Carlos Villaseca, Javier García Serrano, David Orejana   +3 more
doaj   +1 more source

Identification and correlation of the Aso‐3 tephra in the Omaezaki area, central Japan: A valuable key stratum for the MIS 6/5 transition period

Journal of Quaternary Science, Volume 41, Issue 6, Page 972-986, August 2026.
ABSTRACT The Aso‐3 tephra is one of the most significant widespread marker layers from the Middle to Late Pleistocene, generated by a large caldera‐forming eruption at the Aso volcano in Kyushu, southwestern Japan. Despite its importance, a distal co‐ignimbrite ash correlative has yet to be clearly identified, primarily because although volcanic glass ...
Toshinori Sasaki, Takuya Morimoto, Tatsuyuki Ueno, Kazuo Mizoguchi, Norihisa Goto, Hisanori Ominami, Shohei Onaka   +6 more
wiley   +1 more source

Petrogenesis of Tarq-Mazdeh volcanic rocks based on clinopyroxene chemistry (South of Natanz, Urumieh Dokhtar volcanic belt)

Journal of Economic Geology, 2019
Introduction Clinopyroxene is one of the most common of the rock forming minerals. Its long formation period (from the earliest crystallization of magma in the core of phenocrysts to the final microcrystalline crystallization in the rock background) can
Marzieh Ghadirpour, Jamshid Ahmadian, Shahzad Sherafat, Mohammad Ali Mackizadeh   +3 more
doaj   +1 more source

Tracing Continental Basalt Sources and Mantle Processes Using Fe Stable Isotopes

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 8, August 2026.
Abstract Iron (Fe) isotopes have emerged as powerful tracers of mantle source heterogeneity and melting processes, yet the mechanisms producing heavy Fe isotope signatures (high δ57Fe values) in intraplate basalts remain debated. Competing interpretations include partial melting of recycled pyroxenite domains versus carbonate‐induced oxidation of a ...
Yi‐Shan Cheng, Jian‐Qiang Liu, Li‐Hui Chen, Xun Yu, Gang Zeng, Xiao‐Jun Wang, Zhao‐Yang He, Jian Zhao, Frances M. Deegan, Valentin R. Troll, Hong‐Fu Zhang   +10 more
wiley   +1 more source

Vanadium Isotopic Compositions of the High‐3He/4He Baffin Island Lavas

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 8, August 2026.
Abstract The isotopic composition of vanadium (V) in hotspot lavas provides new insight into the source of deep mantle heterogeneities. We measured V isotopic compositions in Paleogene Baffin Island lavas, which erupted above the Iceland plume head, to constrain the mantle plume source. These lavas have V isotopic compositions that are lighter (−0.96 ± 
Jonas Kaare‐Rasmussen, Forrest Horton, Maureen Auro, Andy W. Heard, Sune G. Nielsen   +4 more
wiley   +1 more source

Structurally‐Controlled Permeability Evolution and Mineralization in Geothermal Caprocks: The Fenice Capanne Mining District (Southern Tuscany, Italy)

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 8, August 2026.
Abstract The Neogene mineralized region of the Colline Metallifere in southern Tuscany (Italy) provides a natural laboratory to investigate feedback between fluid–rock interaction, structurally controlled fluid flow, and hydrothermal ore mineralization.
Barbara Marchesini, Federico Rossetti, Ahmad Rabiee, Andrea Billi, Andrea Cavallo, Davide Novella, Vincenzo Moretto, Antonio Caracausi, Fabio Trippetta, Luca Aldega, Luigi Dallai, Giovanni Ruggieri, Eugenio Carminati   +12 more
wiley   +1 more source

Highly Enriched and Heterogeneous Mantle Signals Recorded in Mantle Pyroxenite Veins

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 8, August 2026.
Abstract The Earth's mantle is inherently heterogeneous, reflecting ongoing mantle depletion and crustal recycling driven by plate tectonics. Radiogenic isotopes in oceanic basalts are commonly used to characterize mantle reservoirs, but the full chemical diversity of mantle‐derived melts may be obscured by magma mixing during melt transport and ...
Zhen‐Yu Zhang, Chuan‐Zhou Liu, Yan Liang, Tong Liu, Chang Zhang, Bo‐Da Liu, Wen‐Bin Ji, Wei‐Qi Zhang, Ke Huang   +8 more
wiley   +1 more source