Anomalous variations in the amplitude of a very long wave signal with reference to the earthquake preparation processes

The paper discusses possible short-term precursors of strong earthquakes in the very long wave (VLW) range. Earthquake precursors are shown to occur i n experimental data 9 hours to 3 minutes prior to an event, and their proba bility is higher under stabler geophysical conditions. It is shown that the spatial domain around a VLW path, within which precursors can be observed, is 2 to 2.5 times larger than the domains reported by other authors and de pends on the distance between the path and the earthquake epicenter.