Seismoelectromagnetic signals recorded during an active seismic experiment

The presence of Electromagnetic signals associated with the generation and propagation of mechanical perturbation in the subsoil (Seismo-Electromagnetic signals SES, in what follow) is a matter of fact. An increasing number of scientific papers is focused on this topic and it is quite common to find examples of SES, caused by earthquake occurrence, accidentally recorded during magnetotelluric recording. Considering the unpredictability (in terms of exact occurrence time and location) of the earthquakes, a systematic study on the SES and on their potential use for the subsoil exploration needs dedicated experiments and data analysis techniques tuned on the characteristics of the problem. To this aim, ElectroMagnetic signals were recorded in the margin of a seismic refraction experiment (RICEN, MEDSUV european Project ). RICEN have been conducted in the Solfatara area which is one of the forty volcanoes of the Campi Flegrei (Campania region, Italy). The Solfatara is affected by an intense hydrothermal activity and it is hence a perfect natural laboratory where to test the connection and the influence of fluid presence on the SES. By using MagnetoTelluric (MT) instruments, the SES generated by the controlled seismic source (Vibroseis) have been detected and characterized to investigate the SES propagation and to define a reliable and objective analysis technique.