This project is using Global Positioning System (GPS) repeat observations, and Interferometric Synthetic Aperture Radar (InSAR) to monitor active deformation in Morocco associated with ongoing "collision" of the African plate with Iberia (Eurasia). Additionally, neotectonic and paleoseismic studies are helping better determine the relation between ongoing deformation, earthquake generation, and the development of geologic structures. Toward these ends, the investigators are upgrading three continuous GPS (CGPS) stations (Rabat, Tetouan, Ifrane) and establishing a new CGPS station near Agadir. These stations provide highly precise estimates of Africa (Nubia) plate motion as well as strong constraints on intraplate deformation, including anticipated shortening across the Atlas Mountains in central Morocco. In addition, the Moroccan CGPS network provides a framework for integrating survey-mode GPS observations that provide dense coverage to isolate individual, active structures. The relationship between interseismic deformation (as recorded by GPS and InSAR) and the earthquake cycle are being investigate with paleoseismic techniques. A major focus of our work is the Rif Mountains in northwestern Morocco that exhibit rapid SW motions relative to the African plate as a whole. GPS and InSAR measurements are better defining the special and temporal character of these anomalous motions. Using the improved deformation results, quantitative models to test extrusion models (crust being squeezed out of the collision zone) as well as models of crustal deformation associated with dynamic processes in the mantle (active subduction, lithospheric delamination) are being developed.
