La fábrica magnética de los materiales cambroordovícicos de la parte oriental del anticlinal de la Massana (Andorra, Pirineo Central)

Abstract

The magnetic fabric of the Cambro-Ordovician rocks forming the eastern part of the Massana Anticline (Central Pyrenees) has been determined along with the geometrical relationships with the main field mesoestructures. This constitutes the first set of magnetic data collected in this area and are characterized by a well defined ASM ellipsoids with well defined axes orientation: Kmax , plunges towards the WNW, Kint, towards the ENE or ESE and Kmin is oriented N-S gently dipping or subhorizontal. Magnetic foliation generally coincides with the main cleavage plane and the magnetic lineation is parallel to the stretching lineation and oblique to the intersection lineation. These fabrics are interpreted as formed during the main deformational episode and do not reflect any remain of the sedimentary primary fabric. ASM appears to be an useful and powerful tool in qualitative and semiquantitative determination of strain or kinematic criteria in these rocks.