Atmosphere, ocean and lithosphere interaction as a possible drive of earthquake triggering

Application of spaced system of laser interferometers and tiltmeters for sharing the earthquakes precursory events

“…2 g, h showing the synchronous records of tilts and atmospheric pressure at observation point "Jezeri" JZR one month before the Macquarie Mw 8.1 on 23 December 2004 and Sumatra Mw 9.1 earthquakes on 26 December 2004. Strong anti-correlation (correlation coefficient RP~-0,9) is evidently seen at these records: (1) joint tilt and baric variations on 18-19 December 2004, which correspond to ULF (Ultra-Low Frequency) 0.006 mHz oscillations recorded these days [7,11]; (2) near diurnal tilt-baric variations on 21-24 December 2004 corresponding to significant ionospheric modifications distinguished on 21 and 24 December 2004 [11].…”

“…Observations of earth tilts have been carried out by mean of accurate pendulum tiltmeters installed at tree tidal observatories located in the Bohemian Massif [10,11]. Pribram Observatory (Central Bohemia, observation point PRB in Fig.…”

“…1) is installed in a gallery about 40 m underground, which is located at a junction of Neogene clastic and fractured zone. Two-component tiltmeters measuring earth tilts in NS and EW directions are describe in detail in [10,11]. The resolution of tiltmeters with vertical pendulum is estimated as 1 milliarcsecond (mas) in tidal channel and 0.1 mas in seismic-accelerometer channel.…”

“…2 c, d. Local events and weak global disturbances can be distinguished by means of spatially distributed system of strainmeters and tiltmeters, which are sensitive to precursors of strong seismic and large atmosphere disasters [11,19].…”

“…The subject of presented investigation is the analysis of non-tidal strain-baric and tiltbaric processes recorded by system of ground-based laser interferometers within the Moscow Syneclise (Fryazino, Obninsk) [3,[6][7][8] and Kamchatka Peninsula (Karymshina) [8,9] together with synchronously operating tiltmeter instruments of deep underground installations in the Bohemian Massif (Skalna, Jezeri, Pribram) [10,11]. An applied method includes searching correlations between laser interferometers data and distant tiltmeters data before strong earthquakes.…”