An estimation of the elastic thickness of the lithosphere in the Canary Archipelago using admittance function

Abstract

A recent compilation of shipborne gravity and bathymetry data has been used to determine the Effective Elastic Thickness (EET) of the lithosphere beneath the Canary Islands volcanic complex by means of the admittance technique. As a first approach, we have computed the admittance, which is interpreted in terms of isotropic elastic plate thickness, with an EET of 23 km. Nevertheless, the proximity of the West African Continental Margin (WACM), together with the lateral variability in lithosphere structure in part caused by the large volcanic history of the Canaries, require a slightly different approach. To minimize the influence of the margin and to check whether or not any significant variation in EET occurs related to the known Canary hotspot, we have computed the admittance following the isochron lines. The results show a higher EET (35 km) than that obtained by the first approach but slightly smaller than that predicted by the cooling plate model.