Articles | Volume 11, issue 6
https://doi.org/10.5194/se-11-2377-2020
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https://doi.org/10.5194/se-11-2377-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 Dec 2020
Research article |
| 11 Dec 2020
| 11 Dec 2020
Comparative geochemical study on Furongian–earliest Ordovician (Toledanian) and Ordovician (Sardic) felsic magmatic events in south-western Europe: underplating of hot mafic magmas linked to the opening of the Rheic Ocean
Instituto de Geociencias (CSIC-UCM), Dr. Severo Ochoa 7, 28040 Madrid, Spain
Teresa Sánchez-García
Instituto Geológico y Minero de España, Ríos Rosas 23, 28003 Madrid, Spain
Claudia Puddu
Dpt. Ciencias de la Tierra, Universidad de Zaragoza, 50009 Zaragoza, Spain
Josep Maria Casas
Dpt. de Dinàmica de la Terra i de l'Oceà, Universitat de Barcelona, Martí Franquès s/n, 08028 Barcelona, Spain
Alejandro Díez-Montes
Instituto Geológico y Minero de España, Plaza de la Constitución 1, 37001 Salamanca, Spain
Montserrat Liesa
Dpt. de Mineralogia, Petrologia i Geologia aplicada, Universitat de Barcelona, Martí Franquès s/n, 08028 Barcelona, Spain
Giacomo Oggiano
Dipartimento di Scienze della Natura e del Territorio, 07100 Sassari, Italy
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Emilio González Clavijo, Ícaro Dias da Silva, José R. Martínez Catalán, Juan Gómez Barreiro, Gabriel Gutiérrez-Alonso, Alejandro Díez Montes, Mandy Hofmann, Andreas Gärtner, and Ulf Linnemann
Solid Earth, 12, 835–867, https://doi.org/10.5194/se-12-835-2021, https://doi.org/10.5194/se-12-835-2021, 2021
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In northwest Iberia, a low-grade unit separates the unrooted accretionary prism from the autochthon. It was divided into Upper (preorogenic) and Lower (synorogenic) parautochthons around the Morais Complex. A review of the sedimentary sequence characteristics, supported by U–Pb ages in 17 new samples of synorogenic sediments and volcanic olistoliths, proposes this model to show the Galicia–Trás-os-Montes Zone forming a tectonic carpet exposed in most of the Parautochthon–Autochthon limit.
Stefano Tavani, Pablo Granado, Amerigo Corradetti, Thomas Seers, Josep Maria Casas, and Josep Anton Muñoz
Solid Earth, 11, 1643–1651, https://doi.org/10.5194/se-11-1643-2020, https://doi.org/10.5194/se-11-1643-2020, 2020
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Using orthophotos, we manually digitized 30 000 joints in the eastern Ebro Basin of the Pyrenees. Joints are perpendicular to the belt in the frontal portion of the belt and in the inner and central portion of the foredeep basin. Joint orientations in the external portion of the foredeep become less clustered. Joints in the studied area formed in the foredeep in response to foredeep-parallel stretching, which becomes progressively less intense within the external portion of the foredeep basin.
Josep Maria Casas, Joan Guimerà, Joaquina Alvarez-Marron, and Ícaro Días da Silva
Solid Earth Discuss., https://doi.org/10.5194/se-2020-126, https://doi.org/10.5194/se-2020-126, 2020
Revised manuscript not accepted
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Many orogenic belts exhibit arcuate form in map view. We deal with the different models proposed to explain the formation of the Ibero-Armorican Arc in the western European Variscan Belt. We suggest this arc is primary slightly modified by superposed contraction during late Carboniferous and/or Alpine times. We discuss the role of late-Variscan regional strike-slip faults in the Iberian and in the Armorican massifs that probably acted consecutively before and during the contraction of the arc.
Francisco J. Rubio Pascual, Luis M. Martín Parra, Pablo Valverde-Vaquero, Alejandro Díez Montes, Manuel P. Hacar Rodríguez, Justo Iglesias, Rubén Díez Fernández, Gloria Gallastegui, Nemesio Heredia, and L. Roberto Rodríguez Fernández
Solid Earth Discuss., https://doi.org/10.5194/se-2020-25, https://doi.org/10.5194/se-2020-25, 2020
Preprint withdrawn
G. Mongelli, S. Monni, G. Oggiano, M. Paternoster, and R. Sinisi
Hydrol. Earth Syst. Sci., 17, 2917–2928, https://doi.org/10.5194/hess-17-2917-2013, https://doi.org/10.5194/hess-17-2917-2013, 2013
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Subject area: Tectonic plate interactions, magma genesis, and lithosphere deformation at all scales | Editorial team: Geochemistry, mineralogy, petrology, and volcanology | Discipline: Geochemistry
Magnesium isotope fractionation processes during seafloor serpentinization and implications for serpentinite subduction
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Whole-rock and zircon evidence for evolution of the Late Jurassic high-Sr ∕ Y Zhoujiapuzi granite, Liaodong Peninsula, North China Craton
Bromine speciation and partitioning in slab-derived aqueous fluids and silicate melts and implications for halogen transfer in subduction zones
Boninite and boninite-series volcanics in northern Zambales ophiolite: doubly vergent subduction initiation along Philippine Sea plate margins
Sune G. Nielsen, Frieder Klein, Horst R. Marschall, Philip A. E. Pogge von Strandmann, and Maureen Auro
Solid Earth, 15, 1143–1154, https://doi.org/10.5194/se-15-1143-2024, https://doi.org/10.5194/se-15-1143-2024, 2024
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Magnesium isotope ratios of arc lavas have been proposed as a proxy for serpentinite subduction, but uncertainties remain regarding their utility. Here we show that bulk serpentinite Mg isotope ratios are identical to the mantle, whereas the serpentinite mineral brucite is enriched in heavy Mg isotopes. Thus, Mg isotope ratios may only be used as serpentinite subduction proxies if brucite is preferentially mobilized from the slab at pressures and temperatures within the arc magma source region.
Veronica Peverelli, Alfons Berger, Martin Wille, Thomas Pettke, Pierre Lanari, Igor Maria Villa, and Marco Herwegh
Solid Earth, 13, 1803–1821, https://doi.org/10.5194/se-13-1803-2022, https://doi.org/10.5194/se-13-1803-2022, 2022
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This work studies the interplay of epidote dissolution–precipitation and quartz dynamic recrystallization during viscous granular flow in a deforming epidote–quartz vein. Pb and Sr isotope data indicate that epidote dissolution–precipitation is mediated by internal/recycled fluids with an additional external fluid component. Microstructures and geochemical data show that the epidote material is redistributed and chemically homogenized within the deforming vein via a dynamic granular fluid pump.
Renyu Zeng, Mark B. Allen, Xiancheng Mao, Jianqing Lai, Jie Yan, and Jianjun Wan
Solid Earth, 13, 1259–1280, https://doi.org/10.5194/se-13-1259-2022, https://doi.org/10.5194/se-13-1259-2022, 2022
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In the Liaodong Peninsula, the widely exposed Jurassic high-Sr / Y rocks are generally considered to be derived from the thickened mafic crust. However, research on the Zhoujiapuzi granite in this study shows that there is at least one pluton with a high Sr / Y signature inherited from the source. Zircon growth in Zhoujiapuzi granite can be divided into two stages. The light-CL core was formed in a deeper, hotter magma chamber. The dark-CL rim formed from later, more evolved magma.
Marion Louvel, Carmen Sanchez-Valle, Wim J. Malfait, Gleb S. Pokrovski, Camelia N. Borca, and Daniel Grolimund
Solid Earth, 11, 1145–1161, https://doi.org/10.5194/se-11-1145-2020, https://doi.org/10.5194/se-11-1145-2020, 2020
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Here, we conducted spectroscopic measurements on high-pressure, high-temperature fluids and melts to study how halogens, in particular bromine, can be incorporated in subduction zone fluids and melts. We find that a gradual evolution of bromine speciation with liquid composition enables the incorporation of high amounts of Br in both phases. Thus, bromine and, by extension, chlorine are expected to be efficiently recycled from the slab towards the volcanic arc.
Americus Perez, Susumu Umino, Graciano P. Yumul Jr., and Osamu Ishizuka
Solid Earth, 9, 713–733, https://doi.org/10.5194/se-9-713-2018, https://doi.org/10.5194/se-9-713-2018, 2018
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The occurrence of boninite in the northern Zambales ophiolite is reported. Boninite is a relatively rare high-magnesium andesite that is intimately associated with early arc volcanism and the initiation of subduction zones. Taken as a whole, the geological and geochemical characteristics of Zambales and Izu-Ogasawara–Mariana forearc volcanic sequences enables a refined geodynamic reconstruction of subduction initiation.
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Short summary
A geochemical comparison of early Palaeozoic felsic magmatic episodes throughout the south-western European margin of Gondwana is analysed and includes data from the Iberian Massif, the Eastern Pyrenees, southern France and Sardinia. This dataset favours partial melting of sediments and/or granitoids in the lower continental crust during extensional movements related to the opening of the Rheic Ocean.
A geochemical comparison of early Palaeozoic felsic magmatic episodes throughout the...
