Imaging the crust and uppermost mantle structure of Portugal (West Iberia) with seismic ambient noise

SUMMARY We present a new high-resolution 3-D shear wave velocity (Vs) model of the crust and uppermost mantle beneath Portugal, inferred from ambient seismic noise tomography. use broad-band data dense temporary deployment covering entire Portuguese mainland between 2010 2012 in scope WILAS project. Vertical component are processed using phase correlation weighted stack to obtain empirical Green functions (EGFs) for 2016 station pairs. Further, we random sampling subset stacking strategy measure robust Rayleigh-wave group velocities period range 7–30 s associated uncertainties. The tomographic inversion is performed two steps: First, determine group-velocity lateral variations each period. Next, invert them at grid point trans-dimensional scheme model. final extends upper (5 km) down (60 has resolution ?50 km. In middle crusts, Vs anomaly pattern matches tectonic units Variscan Massif Alpine basins. transition Lusitanian Basin Ossa Morena Zone marked by contrast moderate- high-velocity anomalies, addition arched earthquake lineations. Some faults, namely, Manteigas–Vilariça–Bragança fault Porto–Tomar–Ferreira do Alentejo fault, have clear signature km). Our offers insights into continuation main depth contributes better understanding seismicity Portugal.