ACOUSTIC-GRAVITY MODEL OF THE LITHOSPHERE-ATMOSPHERE- IONOSPHERE COUPLING BEFORE EARTHQUAKES

Meister C.-V.1, Hoffmann D.H.H.1, Liperovsky V.A.2
  1. Technische Universit Darmstadt, Schlossgartenstr. 9, Darmstadt
  2. Institute of Physics of the Earth, Russian Academy of Sciences, Bol'shaya Gruzinskaya str. 10, Moscow

Introduction. In some of the models of lithosphere-atmosphere-ionosphere coupling before earthquakes
it is assumed that atmospheric acoustic and acoustic-gravity waves are generated several days before
earthquakes in earthquake preparation zones and propagate from the Earth's surface through the atmosphere

up to ionospheric altitudes [1, 2]. There, due to collisions between the neutral and charged particles,

disturbances of the charged particle densities are possible. In the ionospheric E-layer, atmospheric acoustic

and acousticgravity waves especially interact with sporadic layers and cause nonlinear current systems.

Investigating the interaction of infrasound waves of seismic origin with sporadic layers is was already found that
observable by ground-based radar stations waves of the Farley-Buneman type may be excited [3, 4].
Besides, in [5] it was concluded, that at E-region altitudes the conversion of sound waves into Alfven
waves is possible.