Radon and metallic aerosols emanation before strong earthquakes and their role in atmosphere and ionosphere modification

Abstract

One of the widely used techniques for earthquakes prediction research is radon concentration measurements within the seismo-active area. Radon concentration gradually grows during several months before a strong earthquake with a sharp increase few days before and abrupt drop few hours before the shock. This phenomenon usually is restricted to the region where the ground water trapped in the vicinity of the region of the earthquake, hollows out due to stress and escapes through the cracks developed. At the same time electromagnetic precursors exist showing the ionosphere modification before the earthquakes. One of them is the phase variations of the VLF signals passing over the region of anticipated earthquake. As it was shown by theoretical calculations this effect is connected with the changing of the conductivity of the “Earth-ionosphere” waveguide. The second effect is the ionosphere peak electron density variations. Scaled for particular local times (3 h, 6 h, 18 h LT) they show very high level of anticorrelation with the radon variations behavior. The observed variations imply existence of a coupling between them and radon concentration in the ionosphere. This coupling is interpreted in terms of modification of electrodynamic properties of atmosphere-ionosphere system before the earthquakes over the seismo-active zone. The atmosphere conductivity changes itself cannot explain the observed variations. The submicron metal aerosols emanated from earth together with radon have great influence on the modification processes. The same combination of radiation and dust occurred during Chernobyl atomic plant catastrophe and similar phase variations of VLF transmitters signal were observed when the signal passed over the Chernobyl plant during active emanation of the radioactive dust from the exploded reactor. Radon and metallic aerosols monitoring over the seismo-active regions could be used for strong earthquake prediction, and their effects on the electrodynamics of atmosphere-ionosphere system can explain the observed variations within the ionosphere.