Variscan recumbent folding of Ordovician plutons in the Malpica-Tui Unit (NW Iberia) .
- Díez Fernández, Rubén
- Martínez Catalán, José Ramón
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.
Bibliographic References
- ARENAS, R., GIL-IBARGUCHI, J. I., GONZÁLEZ-LODEIRO, F., KLEIN, E., MARTÍNEZ-CATALÁN, J. R., ORTEGA-GIRONÉS, E., DE PABLO-MACIÁ, J. G., and PEINADO, M. (1986): Tectonostratigraphic units in the complexes with mafic and related rocks of the NW of the Iberian Massif. Hercynica, II: 87-110.
- COLE, J. W., MILNER, D. M. and SPINKS, K. D. (2005): Calderas and caldera structures: a review. Earth Sci. Rev., 69: 1-26.
- DÍEZ-FERNÁNDEZ, R., MARTÍNEZ-CATALÁN, J. R. and ABATI-GÓMEZ, J. (2006): Plegamiento recumbente en la Serra do Galiñeiro (Pontevedra, NO España). Geogaceta, 40: 3-6.
- FLOOR, P. (1966): Petrology of an aegirine-riebeckite gneiss-bearing part of the Hesperian Massif: the Galiñeiro and sourrounding areas, Vigo, Spain. Leidse Geologische Mededelingen, 36, 203 pp.
- JOHNSON, S. E., SCHMIDT, K. L. and TATE, M. C. (2002): Ring complexes in the Penninsular Ranges Batholith, Mexico and the USA: magma plumbing systems in the middle and upper crust. Lithos, 61: 187-208.
- KRESTEN, P. (1980): The Alnö complex: tectonics of dike emplacement. Lithos, 13: 153-158.
- MARTÍNEZ-CATALÁN, J. R., ARENAS, R., DÍAZ-GARCÍA, F., RUBIO-PASCUAL, F. J., ABATI, J. and MARQUÍNEZ, J. (1996): Variscan exhumation of a subducted Paleozoic continental margin: The basal units of the Ordenes Complex, Galicia, NW Spain. Tectonics, 15: 106-121.
- PIN, C., ORTEGA-CUESTA, L. A. and GIL-IBARGUCHI, J. I. (1992): Mantle-derived, early Paleozoic A-type metagranitoids from the NW Iberian Massif: Nd isotope and trace-element constraints. B. Soc. Geol. Fr., 163: 483-494.
- RIBEIRO, M. L. and FLOOR, P. (1987): Magmatismo peralcalino no Maciço Hespérico: sua distribução e significado geodinámico. In: F. BEA, A. CARNICERO, J. C. GONZALO, M. LÓPEZ-PLAZA and M. D. RODRÍGUEZ-ALONSO (eds): Geología de los granitoides y rocas asociadas del Macizo Hespérico, Ed. Rueda, Madrid: 211-221.