Acoustic, electromagnetic, and neutron emissions as seismic precursors: The lunar periodicity of low-magnitude seismic swarms

Fracto-emission signals (Acoustic Emission AE, Electromagnetic Emission EME, and Neutron Emission NE), triggered by high-frequency pressure waves at the different scales, can be used as a promising tool for environmental protection against seismicity. So far, no reliable method has been developed yet for the successful application of earthquake prediction because the physical mechanism of earthquakes and precursors is at present poorly understood, as well as the estimation of the so-called “earthquake preparation zone”. On the other hand, recent studies are also re-evaluating the possible correlation between seismic activity and lunar periodicity. Since July 2013 an in-situ experimental campaign has started at a gypsum mine located in Northern Italy, revealing the strong seismic forecasting potentialities of the fracto-emission peaks by means of a dedicated monitoring platform and a multi-modal statistical analysis. In the present paper, an innovative interpretation of the earthquake preparation area is proposed, and the new experimental evidences obtained at the gypsum mine are reported confirming the previous results (Carpinteri and Borla, 2017). Finally, the relationship between small magnitude earthquake swarms occurred in the surroundings of the mine and the Moon phases is also investigated.