La estructura del antiforme del Narcea y su relación con los Mantos Occidentales de la zona cantábrica. Parte Iel sector occidental

Abstract

At the studied area, in the Variscan Belt of NW Spain, the limit between the Cantabrian Zone (CZ) and the West Asturian-Leonese Zones (WALZ) outcrops; it is constituted by precambrian rocks and is known as the Narcea Antiform. In this antiform, two sectors are distinguished due to diferences in rock deformation record at each sector. The western sector of the Narcea Antiform is characterized by the superposition of structures, among which the presence of ductile shear zones is remarkable. These ductile shear zones cleaves a previous foliation, generating several different microestructures as crenulation, crenulation cleavage, and mylonitic or phyllonitic foliations, usualy acompained by mineral lineation. The limit between these western and the eastern units is a major thrust.