Geophysical research: article

M.N. Drobyshev1
V.N. Koneshov1
D.V. Abramov1
D.A. Malysheva2
1 Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, Moscow, Russia 2 Vladimir State University named after Alexander and Nikolay Stoletov, Vladimir, Russia
Journal: Geophysical research
Tome: 22
Number: 3
Year: 2021
Pages: 26-34
UDK: 550.831.23:550.312
DOI: 10.21455/gr2021.3-2
Full text
Keywords: high-precision gravimetric observations, microseismic vibrations, root-mean-square deviation, assessment of the effect of microseisms on long-term gravimetric measurements
Аnnotation: Obtaining the most accurate and reliable gravimetric data has always been and remains the main task of gravimetry. One of the main obstacles during ground gravimetric measurements is seismic impact of both natural and technogenic origin. The paper considers the seismic effect on high-precision gravimetric measurements as a removable inter-ference, as well as the option of using seismic stations to assess the suitability of an observation point for con-ducting high-precision gravimetric measurements according to the calculated value of the root-mean-square de-viation of measurements of the vertical channel. In order to obtain the necessary experimental data at the “Zapol-skoye” test site, in the conditions of a geophysical observatory, gravimetric and seismometric measurements were carried out on the pedestal of a first-class gravimetric station with different recording duration and sam-pling frequency. To determine the level of seismic vibrations’ influence on high-precision gravimetric measure-ments, the signal of the gravimeter sensor was simulated using seismic information as input data and the ob-tained series were compared with gravimetric measurements. In the frequency range of 1.7•10–2–6.0 Hz, the value of the correlation coefficient between the series does not fall below 0.9. Experimental results confirm the possibility of using seismometers as a source of additional information about inertial interference when conducting high-precision gravimetric measurements. At the same time, there is a significant decrease in the amplitude of the high-frequency background noise of the gravimetric data. The root-mean-square deviation of the gravimetric readings shows the noise level of the obtained data and is an important characteristic of the accuracy of the performed gravimetric measurements. The possibility of using seismic sta-tions for assessing possible inertial interference at potential points of gravimetric measurements was also con-firmed.
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