Applied Geophysics

Abstract

This course handout provides a comprehensive introduction to Applied Geophysics for Master’s students specializing in Geotechnics. It presents the fundamental principles of geophysical investigation and their application to the characterization of subsurface conditions in civil and geotechnical engineering. The handout first introduces the physical properties of rocks and soils, including density, elastic properties, electrical resistivity, magnetic susceptibility, and electromagnetic properties, as well as the main parameters measured by geophysical techniques. It then examines gravimetric and micro-gravimetric methods, with emphasis on gravity measurements, data acquisition, corrections, and the detection of subsurface density variations and cavities. The electrical methods chapter covers electrical resistivity measurements, electrode configurations, vertical electrical sounding, Wenner profiling, Electrical Resistivity Tomography (ERT), data acquisition, processing, inversion, topographic effects, and monitoring. The seismic methods chapter introduces seismic wave propagation, P- and S-waves, surface waves, seismic prospecting, and refraction and reflection techniques for evaluating subsurface layering and material properties. Finally, the handout presents electromagnetic methods, including frequency-domain and transient electromagnetic techniques, Ground Penetrating Radar (GPR), and Induced Polarization (IP). Particular attention is given to the advantages, limitations, interpretation, and selection of appropriate geophysical methods according to investigation objectives, target characteristics, depth, resolution, cost, and environmental conditions. Overall, the course provides students with the theoretical and practical foundation required to select, apply, and interpret non-destructive geophysical techniques and integrate their results into geotechnical investigations and engineering decision-making.