A 3-D crustal model for SW of Iberia

Abstract:

The Iberian Peninsula is located at the western part of Eurasia-Africa plate boundary. The SW of Iberia is a tectonically complex region, where starts the transition from oceanic to continental plate boundary. The occurrence of large and damaging earthquakes in this zone, such as the 1755 Lisbon (I_max=X) or the 1969 (Ms=8.1), with focus of-shore, some of which generates tsunami shows the interest of this region. In order to carry out detailed studies of seismicity and rupture process of these earthquakes is important to have a detailed crustal model. We have retrieved data from refraction and reflection seismic profiles done in the zone in the last 30 years. With this information we have obtained a 3D model for the SW Iberia (between 10.5ºW to 6ºW and 34.5ºN to 38.5ºN) formed by a grid of 0.5ºx0.5º in horizontal and 1 km interval in depth. To check the model we have relocated the 2007 (Mw=5.9) and 2009 (Mw=5.5) earthquakes occurred in this zone using the standard 2D model and the new 3D model. The results show a best depth resolution using the 3D model.