Seismic instruments: article

Аnnotation: In the winter months 2018-2020 Kola branch of the Federal Research Center “Geophysical Survey of the Russian Academy of Sciences” carried out experiments on the registration of acoustic signals from triggered snow avalanches using infrasonic sensors. The purpose of the experiments was to assess the possibility of recording avalanches by the infrasound method in difficult Arctic conditions. To record the acoustic signals generated by the movement of the snow mass along the slope, groups of three spaced sensors (microphones or microbarographs) were used. At the first stage of work, a wired system based on the Baikal-8 digitizer was used. The experience of using a wired registration system revealed its main disadvantages associated with the complexity of the operational deployment of long wired lines and control of their safety. To reduce the time spent on deploying acoustic avalanche detection system and to improve the reliability and safety of the equipment, a wireless version of the infrasonic array for temporary observations was developed. The wireless system for recording infrasonic signals consists of three modular radio microphones, each of which includes the necessary functional blocks, arranged in a single housing, and transmits data by radio communication to a signal receiver - a base module that contains a controller that transmits data received by radio communication from modular radio microphones, into a computer for collecting and processing data. The created wireless mobile infrasound array was tested in the course of several experiments on the registration of signals from triggered snow avalanches. As a result of the experiments, records of infrasonic signals were obtained at various distances from the avalanche; conclusions were drawn about the applicability of the infrasonic method and the operability of the selected scheme and equipment layout for recording the facts of avalanches. The obtained results will make it possible to proceed to the development and creation of a permanent infrasonic complex for monitoring avalanche activity in the Khibiny mountain range.