GNGTS 2013 - Atti del 32° Convegno Nazionale

to the Cuban Ministry of Construction, and 11,120 geological borings from the Geominera East company (EGMO), collected in a dataset by Mendez et al. (2001). All this information was implemented into a GIS database. d. Geophysics. The information from regional geophysical surveys (aeromagnetic, magnetic, gravimetric, seismic and geo-electric) was taken from Medina et al. (1999). In addition some local geophysical surveys were developed: electrical resistivity (tomography) and seismic refraction, in order to validate the physical-mechanical properties of the soil profiles and the characteristics of the rock basement in terms of VS. e. Topography. All sites have been characterized by their elevation on the basis of the Terrain Elevation Model of the study region. f. Bathymetry. As the study region comprises an offshore sector, it was necessary to use the bathymetric data (Diaz et al. , 1998) to determine the sea depth and in this way to make a better interpretation of the geotechnical profiles that cross the bay area. The geotechnical model for the future modelling of site effects. The final goal of this work is the estimation of the expected ground motion amplification due to the local soil response in the Santiago de Cuba city broader area. To reach this aim, a procedure was designed that accounts for all available information. The bedrock, in terms of layer with a V S greater than 800 m/s, represents the starting layer from which the modelling of the local amplification is computed and it is made of hard or very hard rock, according to physical-mechanical properties. The geometry and the characteristics of the bedrock have been derived from the data of the geotechnical borings (lithology of the different strata and their physical-mechanical properties), the description of the geological formations (Nagy et al. , 1983; Carrillo et al. , 2009), the stratigraphic behaviour, and the geophysical information based on the surveys done. Sixty-one profiles have been constructed to identify the different layers of the sedimentary cover. More precisely, the study area has been divided from north to south and from east to west by a suite of equidistant profiles, with the distance between them fixed at 500 m. We have used a custom VBA code (Create Geologic Cross Sections--eXacto Section v. 2.0, ArcMap 9.3) developed by the Illinois Geological Survey to build-up the geologic cross- sections. The topographic surface (using DEM values), the geologic units and their contact Fig. 2 – 3D representation of the geotechnical model, the superficial geology is represented as in Fig. 1. 332 GNGTS 2013 S essione 2.2