Fig. 2
From: Special issue “The phreatic eruption of Mt. Ontake volcano in 2014”
Results of long-term monitoring of volcanic activity by the Japan Meteorological Agency: a fumarole height based on visual measurements; b fumarole temperature measured at an active vent of the 1979 eruption; c monthly number of earthquakes near the summit of Mt. Ontake. Earthquakes are counted for the same station under a constant criterion using S-P time and maximum amplitude in seismograms