Abstract

Deep seismic profiling and gravity data show that the continental crust under the Valencia trough has been thinned by up to a factor of three in the centre, and that the uppermost mantle there has an unusually low density. Structural mapping in the borders of the Valencia trough shows important asymmetry, and there are asymmetrical features in the geophysical modelling. There are many aspects of the basin formation that are still to be worked out.

Introduction

The past decades have seen a rapid advance in our understanding of the deep structure of extended continental lithosphere. This advance has come primarily because of the integration of geological and geophysical data sets into self-consistent models of basin structure. The investigation of the Valencia Trough is an excellent example of the integrated use of geological and geophysical data to study the structure of a rift-type basin that developed in a region of convergence between the Eurasian and African plates (Fig. 1). The Trough is a small NE–SW-oriented basin in the Western Mediterranean located between the northeastern border of the Iberian Peninsula and the northeastern prolongation of the external zones of the Betic Chain (the Balearic Promontory) (Fig. 1). It is thought to be a basin that formed during a rifting event that began during Late Oligocene–Early Miocene.