THE LITHOSPHERE-ASTHENOSPHERE BOUNDARY OF THE VALENCIA TROUGH (WESTERN MEDITERRANEAN) DEDUCED FROM 2D GEOID AND GRAVITY MODELING

The lithosphere-asthenosphere boundary in the Valencia trough has been investigated by integrated geoid and gravity forward modelling along five regional profiles across the Trough. Our results show that the ba se of the lithosphere maintains an almost constant depth of about 60 k m along the axis of the basin whereas the crust thickens in a NE-SW di rection from 12-13 km to 19 km. These results suggest that a non homog eneous lithospheric stretching mechanism with a greater extension of t he lithospheric mantle was responsible for the opening of the Trough, particularly in the southern area.