Fig. 6
From: Monochromatic infrasound waves observed during the 2014–2015 eruption of Aso volcano, Japan
Spectrograms of infrasound and seismic waves during the 2014–2015 eruption. a Seven-month stacked spectrogram of the infrasound record using reduced data of all the stations to ACM. Data obtained under windy conditions (\(\ge7.74\,\text {m/s}\) at JMA; Fig. 1) are eliminated. Black bar on the left-hand side indicates the period of the 2014–2015 eruption. b Spectrogram of the broadband seismic record of the UMA station. Non-functional stations create data gaps