Rasgos estructurales de la formación granulítica de alta presión de la Bacariza (Cabo Ortegal, NO España)

Abstract

Heterogeneous ductile deformation occurred in the Bacariza formation coeval with hercynian high-pressure granulite facies metamorphism. Eye and anvil fold structures in YZ structural sections have been identified in several outcrops as well as on the map scale. They are interpreted as lineation-perpendicular sections of sheath folds. The mapped foliation trajectory closures produce a variety of geometries defining dome, saddle, basin and inverted saddle configurations, likely related to culminations and depressions of secondary sheath folds within a major one. These sheath-like folded structures might be considered as natural examples of heterogeneous shear in deep subduction/collision channels