INSTRUMENTS AND METHODS OF MEASUREMENT
Application of spatially separated laser strainmeters for recording seismic-strain oscillations of the earth's surface
I. A. Larionova,
D. V. Aleksandrovb,
M. N. Dubrovb,
I. S. Ereminb,
D. S. Kalenovb a Institute of Cosmophysical Research and Radio Wave Propagation FEB RAS; Kotelnikov Institute of Radioengineering and Electronics, Russian Academy of Sciences, Fryazino Branch
b Kotelnikov Institute of Radioengineering and Electronics, Russian Academy of Sciences, Fryazino Branch
Abstract:
The design and installation features of laser strainmeters at «Karymshina» (Kamchatka) and «Fryazino» (Moscow Region) observation points are presented. The main technical characteristics of the strainmeters are confirmed by recording real geophysical processes. The used instruments and methods provide the resolution of
$\epsilon\sim (5-6)\cdot 10^{-11}$ to measure deformations on bases of
$18$ –
$300$ m in length. Based on the results of synchronous observations of microseismic deformations in the frequency band of
$0.4$ –
$4$ Hz, which was carried out in the period preceding the destructive 06.02.2023
$M_w=7.8$ earthquake in Turkey, phenomena of synchronization and restructuring of the spectral composition of the recorded high-frequency microseisms were noted. As a result of the analysis of the deformation-baric processes that accompanied two other strong
$M_w=7.8$ and
$M_w=7.7$ earthquakes, unusual ultra-long-period
$10$ –
$40$-min oscillations with an amplitude approximately an order of magnitude greater than the amplitude of
$L$ and
$R$ seismic waves, and with a characteristic
$7$ –
$8$ min. time delay at point «Karymshina» relative to point «Fryazino» were revealed. The results of the conducted research will be useful in developing methods for preventing natural disasters – earthquakes, tsunamis, hurricanes. Key words: laser interferometers, deformations, microseisms, earthquakes, atmosphere, pressure.
Keywords:
laser interferometers, deformations, microseisms, earthquakes, atmosphere, pressure.
UDC:
551.254:534.23:550.344
MSC: 86A17 Received: 16.04.2025
Revised: 11.06.2025
Accepted: 16.06.2025
DOI:
10.26117/2079-6641-2025-51-2-102-121
Fulltext:
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