Fig. 2From: Seismic velocity decrease and recovery related to earthquake swarms in a geothermal areaTemporal changes in vertical component ACFs at OITA2 station for the frequency range of 1–3 Hz. The number of earthquakes experienced in this region over time (Fig. 1) is shown above for the same period. Phases with positive signs are blue. Arrows mark the onset dates of periods of earthquake activity in mid-June and at the end of October.Back to article page