Uplift and subsidence history of the Alboran Basin and a profile of the Alboran Diapir (W- Mediterranean).

The cooling and subsidence history of the Alboran Basin suggests that it is underlain by a diapiric mantle bulge. Numerical models of crustal doming are applied to investigate the deep lithospheric structure beneath the Alboran Basin. At least two 300 km long high angle faults of E-W strike would be expected directly N and S of the Alboran Sea if the Alboran Diapir had penetrated far into the lithosphere. As there is no record of such faults, it is probable that the Alboran Diapir is a shallow bulge in the lithosphere-asthenosphere interface, which deformed the overlying MOHO. The suggested profile for the deep lithosphere in the Alboran area allows discussion of the details of Weijermars' (1985) model for the tectonic evolution of the Alboran Basin and peripheral Betic-Rif orogens during the past 30-25 Ma. -Author The Hans Ramberg Tectonic Lab, Dept. of Mineral. & Petrol., Inst. of Geol., Univ. of Uppsala, Box 555, S-751 22 Uppsala, Sweden.