Application of laser strainmeters for study of the Earth crust microdeformations in the land-ocean transition zone

摘要

Laser strainmeters allow to register processes in very wide ranges of amplitudes and frequencies, where in most cases they can not be treated as stationary and linear. Using method of empirical mode decomposition and Hilbert transformation, proposed by Huang, measurements of the Earth crust microdeformations, sea level and atmosphere fluctuations were analyzed. Diurnal and semidiurnal maximums are present in the microdeformations and sea level spectra, but they differ considerably in the range of periods less than 6 h. Spectra of air pressure and microdeformations are similar in the range from 6 hours till minutes. A numeric modeling was used to clarify the possible role of internal tides and short internal waves in generation of the crust microdeformations.