Variscan recumbent folding of Ordovician plutons in the Malpica-Tui Unit (NW Iberia) .

  1. Díez Fernández, Rubén
  2. Martínez Catalán, José Ramón
Journal:
Trabajos de geología

ISSN: 0474-9588

Year of publication: 2009

Issue: 29

Pages: 234-236

Type: Article

More publications in: Trabajos de geología

Abstract

A structural analysis in orthogneissic massifs of a subducted fragment of the external edge of Gondwana during the onset of the Variscan collision has been carried out, and reveals the generation of recumbent folds and associated axial planar foliation formed during its exhumation. These folds nucleated in irregular igneous bodies, which were initially deformed during the subduction event, show east to southeast vergence. Down-plunge projection of surface data and series of regularly spaced crosssections have been used to build 3D models of the two main bodies of orthogneiss and to constrain their original igneous shape.

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