Fig. 5
![Fig. 5](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs40623-020-01197-z/MediaObjects/40623_2020_1197_Fig5_HTML.png)
Examples of infrasound signals (the cross-correlation pattern and filtered/unfiltered wave traces from the Chaparral sensor) at ACOLM station compared with photo images at PIRAÑA-AZUFRADO (Pir-Azu in Fig. 1a) camera. Ash emission events on March 1, 2017, at 11:20 (UTC) (a), and on March 28, 2017, at 12:15 (UTC) (b)