Roundup of Global Volcanic Activity
Etna (Sicily, Italy): After several weeks of calm, new activity has started during the past days inside the central Voragine crater. Mild strombolian explosions have been observed from a vent at the bottom of the crater.
Ibu (Halmahera, Indonesia): Our recent group who visited the volcano reports small to moderate explosion from the central vent at intervals of 5-20 minutes.
Aso (Kyushu): While the volcano continues to degas strongly and has intermittent, mostly small ash emissions, a stronger explosion occurred again early on 23 Oct around 6 am local time. An ash plume rose approx. 1.5 km above the Nakadake crater and dissipated quickly. Alert level remains at 3 out of 5, and an exclusion zone of 2 km around the crater is in place.
Bagana (Bougainville Island, Papua New Guinea): Ash emissions occurred from the volcano yesterday, suggesting ongoing mild explosive activity. VAAC Darwin reported a low-level plume extending 50 km northwest from Bagana.
Batu Tara (Sunda Islands, Indonesia): A volcanic ash plume at 5,000 ft (1.5 km) altitude extending 80 km west of the volcano was reported by VAAC Darwin this morning.
Dukono (Halmahera): The volcano continues to erupt continuous, loud, roaring jets of gas and small amounts of spatter from vents at the bottom of the deep crater. Ash plumes are regularly being reported by VAAC Darwin.
Turrialba (Costa Rica): After several months of relative calm, the volcano began to erupt ash plumes again since 23 Oct. Some of the explosions have been relatively strong and caused very small pyroclastic flows limited to the crater area. The origin of these emissions are likely phreatic explosions, i.e. caused by overheated ground water flashing to steam. Whether this is the case or at least some fresh magma is involved is unclear. Seismic activity, which could suggest the rise of new magma, has been reported to have picked up recently.
Cotopaxi (Ecuador): No significant changes have occurred during the past days. The activity remains characterized by intense degassing and occasional mild ash emissions mixed into the plume.
Tungurahua (Ecuador): Mild to moderate ash emissions, with ash plumes rising 1-2 km above the crater, have become more frequent over the past days, suggesting the volcano’s activity has started to picking up. An explosion at 04:33 yesterday morning was seen ejecting incandescent material that rolled down the western flank to up to 1 km distance. Light ash fall occurred later in Chacauco, Cotaló and Manzano. The ash was reported to be black and red in colour and sugary in grain size. The first (colour) suggest that it is from new magma (as opposed to typically gray-brown coloured ash from pulverized older rock). The volcano observatory also reported an increase in seismic activity associated with fluid movements. One possibility is that the volcano (after all, one of the world’s most active ones) enters a more vigorous phase of activity in the near future, as often occurred in the past.