Patterns in the Daily Periodicity of Low Magnitude Seismicity in Kamchatka

摘要

A daily periodicity in small (K ≤ 8.0) Kamchatka earthquakes has been detected, with the maxi-mum occurring during the nighttime. The effect was not observed throughout the area of study, but only in several zones. We show that the results are not affected by human and weather factors. A hypothesis is put for-ward to explain the physical causes of the effect, viz., that the daily periodicity of small earthquakes could be due to natural VLF electromagnetic radiation acting on the geologic medium. It is pointed out that the effect is related to the previously identified effect of natural electromagnetic radiation modulating the intensity of geoacoustic emission from rocks.