Geophysical research: article

A. Belyakov
V. Lavrov
A. Nikolaev
Schmidt Institute of Physics of the Earth, Russian Academy of Sciences
Journal: Geophysical research
Tome: 21
Number: 1
Year: 2020
Pages: 72-88
UDK: 550.348
DOI: 10.21455/gr2020.1-6
Full text
Keywords: seismoacoustic process, vector monitoring, earth tide
Аnnotation: On the Valaam archipelago in Lake Ladoga, in the winter of 2012, a series of telluric acoustic micro events took place. This series was instrumentally recorded by the new device, the Magnetoelastic Inertial Geophone, with a three-component vector characteristic - MIG-3V, which in mid-October 2012 was installed in the rock formation of the Nikolsky Island of the Valaam archipelago and turned on for long-term monitoring. Earlier, separate similar events were repeatedly heard by many residents and visitors of the islands. These events were known for a very long time, and even received an intriguing name - “barantida”, but they could only be instrumentally registered in the winter of 2012 thanks to continuous monitoring. Signal identification was based on the joint use of the received instrumental data and subjective descriptions of this rare phenomenon, previously observed by numerous witnesses of the events. Some characteristic features of the “barantida” are recorded, in particular, the direction to the source of acoustic signals that come from the depth of the underground volume of space, which is located in the northwest direction from the observation point, is determined. The results of an instrumental study of this phenomenon made it possible to compare them with the data previously obtained by us in the Kola superdeep well SG-3 in 2006, when at the end of a continuous monitoring at a depth of 3050 m a seismic-acoustic process with very large amplitudes was found, the shape and duration of which were similar to “barantida”. Recommendations are proposed for continuing research on “barantida” phenomena on the Nikolsky Island of the Valaam archipelago, where an original device with a unique characteristic was permanently installed.