Type of resources
Topographical information about the elements which happen to be in the not build places (topographical network; road and street network; parks, gardens, ...; water, gas, communications networks; sewer system; and some other related information).
Informació about the valid urban planning of the city.
1:5000 city guide
Information about parcels boundaries of the city (houses blocks and parcels boundaries; divisions of these; postal numbers and street names; and some other related information)
Seismic refraction method is based on analyzing the travel times of waves refracted under the critical angle on subsoil interfaces (velocity contrasts). Seismic energy is radiated downwards into the ground from a seismic source on or near the ground surface (e.g. weight drop, explosives,etc.), critically refracted at the interface travelling along it and radiated back to the surface. Observed refracted waves travel-times versus distance are converted into seismic velocity cross-sections of the subsurface.
The Magnetotelluric method (MT) uses natural electromagnetic fields (electrical storms, ionosferic currents) as a source to study subsoil structure. Simultaneous recording of the horizontal electric and magnetic field variations on earth surface allows to determine the electrical resistivity variation as a function of the frequency (depth). Frequency band for MT data ranges from 0.001 Hz to 100 Hz that makes it possible to study depths of up to hundreds of km. For shallow studies (around 1 km investigation depth), control source audiomagnetotellurics method (CSAMT) or audiomagnetotellurics methods (AMT) are required. Frequency band in this type of studies ranges from 1 Hz to 100 KHz.
Borehole geophysical logging techniques are based on measuring and recording continuously the physical properties of interest along a borehole using different probes. Analysis of the correlation between the different records (logs) allows to characterize lithological section and formation fluids.
Vertical Electrical Sounding (VES) is a electrical resistivity method that involves injecting current into the earth and measuring the potential difference between a pair of points. In this way, apparent resistivity of the subsoil as a function of depth can be obtained. VES technique can be applied to a wide range of studies with a maximum investigation depth of about 200 m depending on the acquisition system.