A model of the lithospheric structure of the eastern sector of the Ebro basin has been obtained by means of an inversion of the receiver functions from teleseismic events recorded by one of the Institut d'Estudis Catalans stations located at the northeastern Iberian Peninsula. The technique consists of the isolation and modeling of the amplitude and travel time of the direct P teleseismic wave reverberations in a local structure and has been used for events recorded at Poblet station (POB, placed in the southeast margin of the basin) from 1994 to 1997. The analysis of POB records shows the influence of large-scale heterogeneities in the wave pulses coming from azimuths crossing the Catalan Coastal Ranges, whereas a simple medium response is obtained when teleseismic waves only sample the basin. The inversion of such simple receiver functions in terms of a flat layered media (2- to 3-km layer thicknesses), along with a comparison of the results with previous and independent works, enables us to obtain a crustal and upper mantle velocity structure for the Ebro basin. The preferred solution models show a strong near-surface velocity gradient, a nearly constant P velocity upper crust of about 5.9 km/sec, and a sharp velocity contrast at the crust-mantle boundary located at 32 km depth overlayed by a lower crust consisting of a significant positive velocity gradient. The upper mantle shows an average P velocity of about 8.0 km/sec.

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