PERIODICITIES OF MICROSEISMIC PROCESSES

Abstract

The analysis of digital registering of microseismic background on the geophysical station MHV in 1978-2003 is presented. It is found that time variations of microseismic background are characterized by definite periodicity and quasi-cyclicity. In the frequency range 0.1-10 Hz periodicity 1, 2.8, 8.5 years and 30.5 days is specified, and for the high-frequency component (0.5-40 Hz) - 1 year, 30.5 and 4.9 days, as well as cycles with 3-months length, within which the amplitude variation is changed in the range 25-380 nm/s. Daily amplitude variations are characterized by the average periodicity 24 hours. Along with background microaoscillation amplitude variations, time variations of amplitudes and frequencies of quasiharmonic components are registered.