Roundup of Global Volcanic Activity
Etna (Sicily, Italy): Ash emissions from NE crater continue, but seem to be decreasing in intensity. According to INGV scientists, the volcano had experienced mild inflation prior to the paroxysm last weekend, and this inflation disappeared. The earthquake swarm on the NE side, still ongoing, but also weakening, is thought to be the cause of compression stress, not extension. In that case, the scenario of a new flank eruption on the NE rift in a near future is much less likely. Another of the summit vents seems to be becoming protagonist in the current eruptive phase: the NE crater has been producing near-continous small to moderate ash emissions throughout the night and the morning. Incandescence was occasionally seen at the base of the plumes as well, suggesting strombolian activity. The other vents, in particular Voragine and New SE crater, have been calm. The NE crater, formed in 1911, had not had much significant activity since 1995-1996 when it produced a series of spectacular paroxysms with associated lava flows.
Colima (Western Mexico): Explosive activity at the volcano remains quite intense. On average every 2-3 hours, vulcanian explosions occur from the summit vent, producing ash plumes (often with lightning) of up to 3-4 km height and showering the flanks with incandescent ejecta.
Turrialba (Costa Rica): During the past week, the volcano’s activity has again picked up a bit. New ash emissions, have been occurring again sporadically since 1 Dec. On 7 Dec, an eruption lasting approx. 10 minutes from 13:08 local time produced a dense plume that rose 400 m from the crater and caused light ash fall on the western slope of the volcano. Weak incandescence is visible at night. At the moment, it is unclear if the new activity involved fresh magma or was caused by the volcano’s hydrothermal system.