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https://doi.org/10.5194/se-11-469-2020
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https://doi.org/10.5194/se-11-469-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
03 Apr 2020
Research article |
| 03 Apr 2020
| 03 Apr 2020
Deciphering the metamorphic evolution of the Pulo do Lobo metasedimentary domain (SW Iberian Variscides)
Departamento de Geodinámica, Facultad de Ciencias, Universidad de Granada, Campus de Fuentenueva s/n, 18071 Granada, Spain
Instituto de Ciencias de la Tierra Jaume Almera ICTJA-CSIC, C/Lluís Solé i Sabarís s/n, 08028 Barcelona, Spain
David Jesús Martínez Poyatos
Departamento de Geodinámica, Facultad de Ciencias, Universidad de Granada, Campus de Fuentenueva s/n, 18071 Granada, Spain
Olivier Vidal
Institut de Sciences de la Terre (ISTerre), CNRS-University of Grenoble 1, 1381 rue de la Piscine, 38041 Grenoble, France
Olivier Beyssac
Institut de Physique des Matériaux et de Cosmochimie (IMPMC), CNRS-Sorbonne Université, Case Courrier 115, 4 place Jussieu, 75005 Paris, France
Fernando Nieto
Departamento de Mineralogía y Petrología, IACT, Facultad de Ciencias, Universidad de Granada-CSIC, Campus de Fuentenueva s/n, 18071 Granada, Spain
José Fernando Simancas
Departamento de Geodinámica, Facultad de Ciencias, Universidad de Granada, Campus de Fuentenueva s/n, 18071 Granada, Spain
Antonio Azor
Departamento de Geodinámica, Facultad de Ciencias, Universidad de Granada, Campus de Fuentenueva s/n, 18071 Granada, Spain
Franck Bourdelle
Univ. Lille, IMT Lille Douai, Univ. Artois, Yncrea Hauts-de-France, ULR 4515 – LGCgE, Laboratoire de Génie Civil et géo-Environnement, 59000 Lille, France
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Glauconite and celadonite are green micas which are significant as indicators of palaeoenvironments. They share similar chemical compositions, characterized by their Fe2+, Fe3+ and Mg content despite their white-mica structure; however, the chemical and structural relations were unknown. Their rare coexistence in volcanic rocks due to bacterial activity has allowed us, after an electron microscopy study, to identify a compositional gap between them justified by structural differences.
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Short summary
The metamorphism of the Pulo do Lobo unit (SW Iberian Massif) is described in this paper. To this end, three different and complementary methodologies have been applied. The new results reported here contribute to the knowledge of the metamorphic conditions of the Pulo do Lobo unit in relation to its deformation. Furthermore, the results are compared in order to assess the reliability of the different methods applied.
The metamorphism of the Pulo do Lobo unit (SW Iberian Massif) is described in this paper. To...
