Our sister company Géophysique GPR specializes in refractive seismic studies as part of research in engineering, geotechnics and geology. The seismic refraction method for profiling bedrock is also applicable to marine environments, whether it is a peaceful lake or impassable rapids. Seismic refraction data is typically collected in hydroelectric and engineering projects where bedrock depth and fracture and shear zone information is critical. Seismic reflection, on the other hand, is ideal for mapping stratigraphic layers. The principle of seismic reflection extends from very high resolution profiling of shallow seabed sediment layers to deep geological mapping. 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. A seismic study of shear waves provides geotechnical parameters on seabed sediments for engineering projects.