BIBLIOS

Document type
Journal articles

Document subtype
Full paper

Title
Structural and microstructural analysis of the Retortillo Syncline (Variscan belt, Central Iberia). Implications for the Central Iberian Orocline

Participants in the publication
Ícaro Dias da Silva (Author)
Dep. Geologia
IDL
IDL
Juan Gómez-Barreiro (Author)
José R. Martínez Catalán (Author)
Puy Ayarza (Author)
Jorg Pohl (Author)
Enrique Martínez (Author)

Summary
The Retortillo Syncline is part of a major late-Variscan structure that runs for > 120 km from Figueira de Castelo Rodrigo (Portugal) to Tamames (Spain), affecting Neoproterozoic and Lower Paleozoic metasediments in the Central Iberian Zone, and delineated by the Armorican Quartzite. This tectono-metamorphic study gives new insights on the Variscan evolution of this region, showing that it was affected at least by two contractional Variscan stages (C1 and C3) and by one extensional (E1). The first contractional event (C1), and perhaps an overriding thrust sheet (C2), presently eroded, produced a low-grade Barrovian assemblage (M1) and induced enough load to trigger the formation of high temperature–low pressure (HT-LP) thermal domes (M2) that characterize the regional syn-orogenic extensional event (E1). This allowed the appearance of typical minerals such as andalusite, biotite and/or cordierite. Later, during the C3 stage, the HT-LP isograds were folded and sheared together with the metasediments and a new axial planar slaty cleavage developed surrounding the M2 blasts. Finally a late- to post-kinematic thermal (MT) event associated with the intrusion of a late-Variscan granodiorite led to the growth of new HT-LP minerals and rim overgrowths around previously formed porphyroblasts in a contact metamorphic aureole. The fabric-porphyroblast relations confirm that the Retortillo syncline forms part of a major C3 fold. Interestingly, it is located at the hinge zone of and arcuate structure whose existence is currently under discussion, the Central Iberian Orocline.


Institution
Instituto Dom Luiz (IDL), Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749–016, Lisboa, Portugal

Where published
Tectonophysics

Publication Identifiers
ISSN - 0040-1951

Publisher
Elsevier BV



Document Identifiers
DOI - https://doi.org/10.1016/j.tecto.2017.07.015
URL - http://dx.doi.org/10.1016/j.tecto.2017.07.015

Rankings
Web Of Science Q2 (2018) - 2.764 - GEOCHEMISTRY & GEOPHYSICS - SCIE
SCIMAGO Q1 (2018) - 1.481 - Geophysics
SCIMAGO Q1 (2018) - 1.481 - Earth-Surface Processes
SCOPUS Q1 (2017) - 1.611 - Geophysics
SCOPUS Q1 (2017) - 1.611 - Earth-Surface Processes
SCIMAGO Q1 (2019) - 1.529 - Earth-Surface Processes
SCIMAGO Q1 (2019) - 1.529 - Geophysics
SCOPUS Q1 (2019) - 5.9 - Geophysics
SCOPUS Q1 (2019) - 5.9 - Earth-Surface Processes
Web Of Science Q2 (2019) - 3.048 - GEOCHEMISTRY & GEOPHYSICS - SCIE

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