PLIOCENE UPLIFE OF THE EASTERN IBERIAN MARGIN - INFERENCES FROM QUANTITATIVE MODELING OF THE VALENCIA TROUGH

We present the results of quantitative modelling of subsidence in the Valencia Trough and associated uplift in the Catalan Coastal Ranges an d the Balearic Islands. Basement subsidence, Moho depth and gravity an omalies are calculated for different effective elastic thicknesses (ee t) and durations of rifting, along two profiles constrained by recentl y collected multichannel seismic and gravity data. The tectonic evolut ion of the Catalan Coastal Ranges cannot be explained with traditional two-layer lithospheric stretching models for the Valencia Trough, but is consistent with a thermomechanical model invoking lithospheric nec king, combined with a late-stage uplift event. The modelling of the to pography of the Balearic Islands suggests an interaction of extension in the Valencia Trough with extension in the South Balearic Basin. Our study supports a rifting model with low values for the flexural rigid ity, an intermediate level of necking and one finite duration stretchi ng event propagating from the northeast towards the southwestern part of the Valencia Trough. The modelling provides constraints on the magn itude of a large-scale Pliocene uplift of the eastern margin of the Ib erian Peninsula.