Cuantificación de deformaciones recientes en el este de la Península Ibérica mediante la comparación de datos de nivelación de precisión

Abstract

The comparison of the Instituto Geográfico Nacional of Spain high precision levelling data measured during the present century allows us to quantify the ve rtical deformations occurred within this period. The vertical displacements are shown as recent ve rtical movement profiles. We studied the eastern Iberian Peninsula due to its historical and instrumental seismicity and because of the presence a moderate tectonic activity. The magnitude of the vertical movements are according to the recent tectonic activity of each zone, thus the greatest deformations are located at the most tectonic active zones. In the central zone (Valencia Through) tectonic deformations are almost inappreciable, but in the northern (Eastern Pyrenees) and southern (Eastern Betics) zones the average vertical velocities range between 1 and 4 mm/year. In the northern zone the ve rtical anomalies are associated with NW-SE and NE-SW faults with a normal component of movement. In the Eastern Betics the anomalies are related to nearly E-W inverse faults and to NE-SW or NW-SE normal faults. These movements agree with the present day stress tensor (NNW-SSE horizontal compression together with ENE-WSW extension). To confirm the obtained results and to have a better understanding on the main active faults we must carry out new levelling lines and more geological studies.