Studies of the Poltava seismic-tidal records during the period of explosions events in Balakliya and Kalynivka
The seismic-tidal records obtained at the Poltava gravimetric observatory of the IGF NAS of Ukraine (PGO) studied before, during and after events in Balaklija (March 22-23) and in Kalinovka (September 26-27) 2017 (explosions in ammunition dumps). Digital records were obtained with seismotiltmeters of compensating type and vertical seismometer (horizontal and vertical components), with thermal barograph and upgraded GS-11 gravimeter. Data analysis is performed by filtration, spectral, correlation and other methods, and the results are presented by graphs. The study of seismic deformation effects during explosions in military depots is a geophysical problem, the solution of which allows parameterize such dangerous events. However, despite its importance and social significance, it is not developed yet and needs additional studies. The analysis of the current-interval correlation functions and spectra shows that in the records up to 23:00 UTC 22.03.17 and 19:00 UTC on 26.09.17 (before the explosoins), the correlation coefficients (K) for short test correlator sections are smaller than 0.2. That is, no significant correlation on the selected interval correlators is observed. The number of pulse-wave seismic packets after a specified time, increases substantially, and seismic packets become clearer in current-interval correlation functions. They also appear in places where because of the noise they are not visible on the primary records. The correlation co-efficient between seismic packets in certain case, increases (K > 0.6  0.8). This indicates the similarity of the pulsed wave packets and that they are generated in one place and have the same physical origin: obviously it is an explosion. The research has revealed the characteristic singularity of the seismodeformation signals during these events. A methodology for studying them has been developed. Many fundamental and applied problems have remained out-of range and must be investigated. Earth’s crust interaction - atmospheric explosion, energy of charges and their influence on spectra, residual jumps - deformations, etc. have not been investigated because of limited resources.