Fig. 4: Seismicity and deformation associated with the onset of eruption on 26 June 2018.
From: Caldera resurgence during the 2018 eruption of Sierra Negra volcano, Galápagos Islands
A Azimuth of earthquake epicentres from centre of caldera and focal mechanisms of earthquakes as a function of time (UTC). Circle size indicates magnitude, as in Fig. 3B. Vertical dashed lines indicate timing of the Mw5.4 earthquake (blue), onset of seismic swarm (green), and onset of tremor pulses (red). B Tilt recorded at station SN14 (for tiltmeter location, see Fig. 1E). C Deformation recorded at cGPS stations GV09 and GV03. Before 09:15, all components plot at zero. D Earthquake epicentres, focal mechanisms, and horizontal (black) and vertical (red) cGPS displacements between 08:00 and 12:00, including the Mw5.4 earthquake. Red focal mechanism is the teleseismic Harvard CMT solution. E as D for the period 12:00–21:00. Extent of lava flows shown in red.
