Ground Deformation Detected by Permanent Tiltmeters on Mt. Etna Summit: The August 23-26, 2018, Strombolian and Effusive Activity Case

Figure 5

Volcanic tremor (a) and tilt components at the three stations (b). Red dashes mark the measured reference points for tilt changes (see also Table 2). Numbers indicate the preactivity (0), main variations , minor changes , and end of activity phases. Inset reports the magnification of the small fast variation recorded at ECP and PLC just before onset of volcanic activity.