(a) Vertical sections of the V_P model. The traces of the sections are shown in Fig. 1. Contours lines are at 4.5, 5, 5.5, 6, 6.5, 7, 7.7, 8 km s⁻¹. Seismic hypocentres located less than 10 km from each section are projected. (b) Vertical sections of the V_s model. The traces of the sections are shown in Fig. 1. Contours lines are between 2.75 and 4.75 km s⁻¹, spaced of 0.25 km s⁻¹. Seismic hypocentres located less than 10 km from each section are projected.