A seismic refraction survey consists in causing a transient vibration at the surface and in recording the passage of seismic waves over time, using specific sensors. These waves are reflected or refracted to changes in elasticity and / or density at the boundaries of geological layers. The data processing makes it possible to determine the propagation speeds of seismic waves through the different layers of materials, as well as their depth. The seismic refraction method relies on measuring the shortest time for an induced seismic pulse to travel from the location of its source to a series of receivers. From these travel times, the seismic speeds and depths of the various layers can be calculated. Seismic refraction is the best method for accurately mapping rock depth under most conditions The seismic refraction method is used to obtain a profile of the buried rock and locate fault or shear zones there. These techniques are mainly used for: Seismic refraction applications include: Calculation of the modulus of elasticity of different layers; The determination of the thickness of the layers of unconsolidated deposits; Determination of the depth of the water table; Identification of subvertical geological contacts; Rock profiling and localization of faults and fracturing zones. Seismic refraction surveys can be performed on water even in areas of rapids; Identify subvertical geological contacts. If the information sought concerns the interior of the rock, one or more alternative methods considered will be reflection seismic, seismic tomography or resonance seismic.