There is close relationship between infrasonic wave and natural events and human being activities. As early as in 1960s, scientists of Institute of Acoustics, Chinese Academy of Sciences (IACAS) began the researches on infrasound detection, atmospheric infrasound propagation, infrasound damage effect and so on. In recent years, in collaboration with Beijing University of Technology, China University of Geosciences, etc., IACAS set up several sound inspection stations in Beijing, Hunan and Taiwan and observed the infrasonic waves by a wide-spread sensor network array consisting of broadband infrasound microphones for about 5 years.

According to continuous observations and statistic analyses, the researchers found a kind of low-frequency atmospheric infrasonic waves, which could be possibly associated with some natural events closely. They analyzed the waveforms, spectra, time-frequency chars and correlations among sensors of these infrasonic waves and got the results, which shows that these waves occur either in one group or intermittently in several groups with frequency in a range of 0.001~0.02 Hz and amplitudes in a range of 50~200 Pa. Besides, such infrasonic waves were observed previous to several strong earthquakes, such as Yutian earthquake on Mar. 20th 2008, Wenchuan earthquake on May 12th 2008, Shan-Gan-Chuan border earthquake on Oct. 29th 2009, and so on. The research result provides new reference for the researches on diversity of atmospheric infrasound and correlations with natural events, especially for seismic information detection.