Tilt observations on the Kamchatka Peninsula in 2012–2016
P.P. Firstov1,
E.O. Makarov1,
V.E. Glukhov1,
N.N. Titkov1,
N.A. Zharinov2,
H. Takahashi3
1 Kamchatka Branch, Geophysical Survey, Russian Academy of Sciences, Petropavlovsk-Kamchatsky, Russia
2 Institute of Volcanology and Seismology, Russian Academy of Sciences, Petropavlovsk-Kamchatsky, Russia
3 Institute of Seismology and Volcanology, Hokkaido University, Sapporo, Japan
Corresponding author: P.P. Firstov, e‑mail: firstov@emsd.ru
Abstract. The paper presents the results of tilt-measuring observations on the Kamchatka Peninsula in the period 2012–2016. Of the 6 tiltmeter stations operating in this period, two were successful, located in the area of the Klyuchevskaya group of volcanoes, in which tiltmeters were installed taking into account technical requirements. During the period under consideration, two significant geodynamic events occurred on the Kamchatka Peninsula: the Okhotsk Sea earthquake with MW=8.3 and a source depth of 630 km; Fissure Tolbachik eruption named after the 50th anniversary of the Institute of Volcanology (FTE-50). The simultaneous occurrence of the anomaly, which can be attributed to the precursor, in the behavior of the tilts at two points, and the remote foreshock activation in Avacha Bay, indicate a single geodynamic process of a regional scale preceding the Okhotsk Sea earthquake. At the point closest to the FTE-50 eruption (distance about 40 km), on the N–S component, there is a well-pronounced anomaly that began 5 months before the eruption, which demonstrates a positive tilt of ~70 mсrad. This indicates the complex geodynamic processes occurring before the eruption of FTE-50, which are caused by the migration of magma in layers with neutral buoyancy according to the geophysical model of the magmatic feeding system of the Klyuchevskaya group of volcanoes. The obtained tilts data indicate that they can be a very significant addition to the modern method of observing the movements of the earth's surface using GPS technology.
Keywords: deformation, earth surface, tiltmeter, volcano, strong earthquake, Kamchatka
Funding
This work was supported by the Ministry of Education and Science of the Russian Federation (within the framework of state task No. 075-00576-21) and using data obtained at the unique scientific installation “Seismic-infrasound complex for monitoring the Arctic permafrost zone and a complex for continuous seismic monitoring of the Russian Federation, adjacent territories and the world” (https://ckp-rf.ru/usu/507436/, http://www.gsras.ru/unu/) as well as with the support of the Russian Foundation for Basic Research grant No. 20-05-00493.
About the authors
FIRSTOV Pavel Pavlovich – Kamchatka Branch, Geophysical Survey, Russian Academy of Sciences. Russia, 683006, Petropavlovsk-Kamchatsky, Piip blvd. 9. E-mail: firstov@emsd.ru
MAKAROV Evgenii Olegovich – Kamchatka Branch, Geophysical Survey, Russian Academy of Sciences. Russia, 683006, Petropavlovsk-Kamchatsky, Piip blvd. 9. E-mail: ice@emsd.ru
GLUKHOV Vitalii Evgenevich – Kamchatka Branch, Geophysical Survey, Russian Academy of Sciences. Russia, 683006, Petropavlovsk-Kamchatsky, Piip blvd. 9. E-mail: glukhov_v@emsd.ru
TITKOV Nikolai Nikolaevich – Kamchatka Branch, Geophysical Survey, Russian Academy of Sciences. Russia, 683006, Petropavlovsk-Kamchatsky, Piip blvd. 9. E-mail: nik@emsd.ru
ZHARINOV Nikolai Alekseevich – Institute of Volcanology and Seismology, Russian Academy of Sciences. Russia, 683006, Petropavlovsk-Kamchatsky, Piip blvd. 9. E-mail: nzhar@kscnet.ru
TAKAHASHI Hiroaki – Institute of Seismology and Volcanology, Hokkaido University. E-mail: hiroaki@mail.sci.hokudai.ac.jp
Cite this article as: Firstov P.P., Makarov E.O., Glukhov V.E., Titkov N.N., Zharinov N.A., Takahashi H. Tilt observations on the Kamchatka Peninsula in 2012–2016, Seismicheskie Pribory, 2021, vol. 57, no. 1, pp. 49–68. (in Russian). https://doi.org/10.21455/si2021.1-4
English translation of the article will be published in Seismic Instruments, ISSN: 0747-9239 (Print) 1934-7871 (Online), https://link.springer.com/journal/11990)