A deformação varisca do Maciço Hespérico na região da Serra da Lousã (Portugal central)

Abstract

[Abstract] The occidental region of the Central-Iberian Zone of the Variscan Iberian massif, in the central part of Portugal (Lousã mountain range), has a Variscan tectonostructural organization as the one recognized in the occidental border of the massif, in the Porto-Coimbra-Tomar shear zone. In the Iberian massif we can observe neo-proterozoic metasediments of the “Complexo Xisto-Grauváquico”, and important metasedimentary outcrops of Late Palaeozoic (Ordovician, Silurian and lower Devonian) rocks. Both are affected by the first regional variscan deformation phase (FH1), and later refolded by the second variscan deformation phase (FH2). This second regional variscan phase has a penetrative effect in the massif and develops a dextral, north-south, strike-slip faulting, associated with transpressive kinematic deformation (like a Riedel model) similar to the Porto-Coimbra-Tomar shear zone. Some geological examples observed and studied in the Lousã region are showed and discussed.