One way to cover a more significant area extension is by seismic tomography. We took advantage of the semi-enclosed array in the study area to create a Vp tomography of refracted arrivals and another of Vs using dispersion curves, both active source tomographies. Figure 3a shows the selection of the first arrivals of all refraction records using. Direct arrivals show that Vp in the first layer is approximately 400 m/s. Refracted arrivals (after a critical distance of 20 m) exhibit large dispersion, indicating the bedrock is irregular with a Vp average of 1200 m/s according to the values in Figure 2. Figure 3b shows the velocities representation of the discretized model. The bedrock average depth is 8 m. A higher velocity zone is observed in the northern part of the array, between 8 and 10 m depth with Vp reaching up to 3000 m/s.