Tectonic and geodynamic significance of paleomagnetic rotations in the Iberian Chain, Spain

Abstract

Las evidencias obtenidas en calizas del Jurásico Superior de la Cadena Ibérica sobre (a) una componente magnética secundaria (cretácica) diferente de la magnetización primaría y (b) rotaciones locales de eje vertical de ambas componentes, delimitan en parte la historia evolutiva del movimiento de la Placa Ibérica e implican una reconsideración del concepto de "Iberia estable". La coexistencia de sitios rotados y no rotados apoya además un modelo tectónico de convergencia oblicua con relaciones diferenciales entre cobertera y basamentoEvidence from Late Jurassic limestones of the central Iberian Chain for (a) a secondary (Cretaceous) magnetic component different in declination by some 75° (clockwise) from the direction of the primary magnetization, and for (b) local vertical-axis rotations of both these components, provides additional constraints on the history of motion of the Iberian Plate and implies a reconsideration of the concept of «stable Iberia». Moreover, the coexistence of rotated and non-rotated sites across the Iberian Chain supports a tectonic model of intraplate oblique convergence and differential cover-to-basement relationships