Electromagnetic Methods in Geophysics: Applications in GeoRadar, FDEM, TDEM, and AEM

The shallow part of the subsoil, either natural as well as urban or industrial, is impacted by a large number of interactions and interferences on a daily basis, worldwide, because of anthropogenic activities. Excavations, trenching and digging for building constructions, road maintenance, archaeological, urban development, forensic, cavity search, ore bodies search, geological, geotechnical and engineering purposes are conducted every day all over the world. The a-priori knowledge of the subsoil is often poor or non-existing, hence the need for (non-destructive) techniques for the enhancement of the model of the soil, prior to excavation. There are several geophysical techniques whose deployment aims at defining such models, and many of them, for their implementation on site, makes use of sensors to be coupled with the soil (embedded, like geophones for seismic refraction and reflection, or electrodes for Electrical resistivity methods). One of the main advantages of the whole family of the Electromagnetic (EM) methods is because they do not make use of any embedded sensor, fixed on top of the soil surface. This makes the technique fast, non-destructive, and highly productive from the data acquisition point of view. The applicability of the "EM family" methods is rather wide, and ranges from utility mapping, to cavity detection, pollutants search, UXO search, Volcanogenic Massive Sulphides (VMS) search, geotechnical engineering applications and so on. The dimension of the areas that can be covered varies from a few squared meters, for detailed studies with high resolution, to thousands of squared meters for exploration that can reach down to hundreds of meters in depth (for Airborne EM Techniques) for the search of targets of a larger size. Electromagnetic Methods in Geophysics: Theory and Applications provides a general introduction to the electromagnetic methods in several application fields. Physical and mathematical principles and fields of applications are well-explained, and the field acquisition procedures, data processing and interpretation, are illustrated to guarantee the best understanding of the results, on a layman perspective.