Ambient Seismic Noise Analysis Associated with the 2010 Eruption of Merapi Volcano Using Temporal Variations of Randomness and Background Noise

Figure 3

Temporal variations of PE and PSD for PUS and DEL stations. The 2010 Merapi eruption was not preceded by a significant reduction in signal randomness. The character of the events in the preeruptive period and the crisis tend to be chaotic. PSD fluctuations in the low-frequency band almost always coincide with variations in the high-frequency band. Two primary eruption onsets correspond to the two highest PSD peaks, both in the low and high-frequency bands.