Partição da deformação Varisca nos sectores de Peso da Régua e Vila Nova de Foz Côa (Autóctone da Zona Centro Ibérica) Strain partitioning of Variscan deformation in the Peso da Régua and Vila Nova de Foz Côa region (Centro Iberian Zone autochthon)

The first and main Variscan deformation phase in Marao-Vila Nova de Foz Coa axis (Centro Iberian Autochthon) induced the formation of wide zones gently folded bounded by coeval narrow bands emphasizing stronger deformation. These bands are associated with a WNW-ESE shear zones with a sinistral kinematics. In the Douro Group Cambrian formation of Peso da Regua and Vila Nova de Foz Coa sectors, is possible to see a clear relationship between the narrow bands emphasizing stronger deformation and the regional sinistral shear zones. This geometry shows an extensive area with strong strain partitioning which emphasize the presence of a regional major structure. Such structural pattern characterizes the axial zone of the flower structure, create by the sinistral transpressive regime in northern sectors of the Centro Iberian autochthon during the Variscan orogeny. This structure is here named Douro Flower Structure. The lateral continuity of this regional structure from Marao to Vila Nova de Foz Coa that was possible to put in evidence by this work is interrupted by NNE-SSE Tardi-Variscan sinistral shear-zones, that are reactivated during the Alpine Orogeny.