Discrimination of natural and anthropogenic events by the joint analysis of seismic and infrasound data

Hungary’s first infrasound station began operation in May 2017 at Piszkés-tető in the Mátra Mountains, maintained by the HUN-REN FI Kövesligethy Radó Seismological Observatory. The station detects low-frequency acoustic waves (infrasound; f < 20 Hz) that are inaudible to the human ear. Infrasound is generated by numerous natural and anthropogenic sources, including volcanic eruptions, meteors, thunderstorms, explosions, rocket launches, and planes. A key characteristic of infrasound is its ability to propagate over very long distances in the atmosphere: strong signals may be detected thousands of kilometres from their sources. Atmospheric infrasound monitoring has a wide range of scientific and practical applications. Beyond identifying infrasound sources (e.g., explosions, remote volcanic activity), these waves can also be used to study the structure of the atmosphere, analogous to how seismic waves provide insight into the Earth’s interior. Infrasound research is a relatively young scientific discipline on a global scale. Although its origins trace back to the early 20th century, the field gained significant importance due to the Comprehensive Nuclear-Test-Ban Treaty (CTBT) in 1996. To support verification of the Treaty, a global monitoring network (the International Monitoring System, IMS) was established, which—alongside seismic, hydroacoustic and radionuclide technologies—includes 60 planned infrasound stations dedicated to the detection of nuclear explosions. Currently 54 of them are operational. Over the past two decades, in addition to the IMS stations, numerous smaller research-oriented infrasound arrays have been installed worldwide, and the study of atmospheric infrasound has evolved into an important scientific domain. In Europe, researchers working in this field collaborate within the Atmospheric dynamics Research InfraStructure in Europe (ARISE) project, aimed at high-resolution modelling of the atmosphere through the integration of multiple observational technologies. Our institute joined the project in 2016. One year after the installation of the Piszkés-tető station, our group initiated the establishment of the Central and Eastern European Infrasound Network (CEEIN), which currently includes the Hungarian station, three Romanian stations, two Czech stations, an Austrian station and three Ukrainian stations. The Piszkés-tető array is composed of four microbarometers, optimized for detecting regional events within a range of approximately 1–2000 km. Observations have included numerous domestic mining blasts, thunderstorms, bolides, Eruptions of Mount Etna etc. A primary objective of our team is the monitoring of domestic mining explosions and their discrimination from natural earthquakes through the joint interpretation of seismic and infrasound data. The establishment of the project was supported by the National Research, Development and Innovation Fund of Hungary (project K 128152), and the research effort continues to advance steadily today.

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Last Updated: 18 November 2025