To view the results from this work please go here. The diffuse boundary between Africa and Iberia is a type-example of the complex deformation associated with convergence of continental plates. This boundary includes the Moroccan Rif and Spanish Betic interplate mountain belts, which together constitute the Gibraltar Arc, and the Alboran Sea. Deformation continues today, evidenced by both shallow and intermediate depth seismicity. A number of competing models have been suggested to explain the apparent coeval development of these striking arcuate fold and thrust mountain belts and the neighboring Alboran basin since the early Miocene.
Possible models range from trapped microplates to subduction or delamination.
Such models can be discriminated by a detailed investigation of the lithospheric structure and the seismotectonics of the area. The proposed evolutionary models make predictions of the present spatial distribution and characteristics of seismicity, seismic wave velocities, and attenuation. We are mapping these attributes in three dimensions in order to test these predictions, and develop a constrained geodynamic model for the region. Using the two station method to measure seismic wave velocities and study Sn attenuation to map upper mantle structures and the lateral extent of previously suggested asthenosphere-crust contacts, and using digital waveforms to estimate Q. Performing a high resolution tomographic inversion for the velocity and attenuation structure. This research project involves close collaborative work with both Moroccan and, for the first time, Spanish research institutions.