RT Journal Article
T1 Orogenic reworking and reactivation in Central Iberia: A record of Variscan, Permian and Alpine tectonics
A1 Moreno Martín, Diana
A1 Díez Fernández, Rubén
A1 Vicente Muñoz, Gerardo de
A1 Fernández Rodríguez, Carlos
A1 Gómez Barreiro, Juan
AB Interference between orogenic systems and deformation phases within them may lead to reworking and reactivation of previous structures. The eastern sector of the Spanish-Portuguese Central System holds evidence of two orogenic systems, Variscan and Alpine, plus a stage of Permian extension. We perform an integrated structural analysis to identify reworking and reactivation processes throughout the geological record. The Variscan record starts with crustal thickening (D1; E-verging overturned folds). A second phase features the intra-orogenic collapse of an overthickened crust (D2; top-to-the-SE ductile extensional shear zone), which produced intense structural reworking at the core of the shear zone and moderate reworking at its hanging wall. During subsequent strike-slip tectonics, crustal thickening parted transpressional deformation into a dextral shear zone and upright folds (D3). Variscan deformation did not reactivate previous structures, but exploited a weak rheological boundary defined by contrasted lithologies (sedimentary versus igneous rocks) to accommodate D2 shearing. Reactivation played a role afterwards: Variscan strike-slip shear zone acted as a transfer fault to accommodate Permian extension (post-orogenic collapse), and then Alpine contraction. The Permian extension record is blurred by Alpine inversion, although the trend of Alpine structures in Central Iberia, and the Spanish-Portuguese Central System, may result from Permian structural inheritance.
PB Elsevier
SN 0040-1951, online ISSN: 1879-3266
YR 2022
FD 2022-11-20
LK https://hdl.handle.net/20.500.14352/72566
UL https://hdl.handle.net/20.500.14352/72566
LA eng
NO CRUE-CSIC (Acuerdos Transformativos 2022)
NO Ministerio de Ciencia e Innovación (MICINN)
NO Universidad de Salamanca
DS Docta Complutense
RD 23 jul 2024