Roundup of Global Volcanic Activity:
Tjörnes Fracture Zone (North of Iceland): The earthquake swarm has decreased in intensity. At least some scientists believe that the cause has been a magmatic intrusion in Iceland’s northern rift zone that activated the Húsavík-Flatey (HFF) transform fault at the southern limit of the TFZ where the earthquakes were concentrated.
Batu Tara (Sunda Islands, Indonesia): Ash explosions regularly produce plumes up to about 7,000 ft (2.1 km) altitude, such as this morning. Activity (strombolian-type) on the remote island remains strong.
Dukono (Halmahera): An eruption produced an ash plume observed on satellite data. Estimated altitude was 6,000 ft (1.8 km). (VAAC Darwin)
Popocatépetl (Central Mexico): No changes in the currently low activity have occurred. Moderate steaming, occasional weak ash venting / small explosions (at rates of approx once / 2 hours) and glow at the summit at night characterize the current phase. CENPARED’s alert level remains “Yellow Phase 2”.
Santa María / Santiaguito (Guatemala): INSIVUMEH reported no explosions and no movements at the blocky lava flows on the dome’s flanks, but heavy rainfalls inhibit detailed observations. Strong degassing is observed.
Pacaya (Guatemala): (Strombolian) Explosions occur every 3-5 seconds, INSIVUMEH reports.
Fuego (Guatemala): Activity is very low. Almost no explosions have occurred recently. The lava flow on the upper south flank seems to be still weakly active.
Sangay (Ecuador): During a recent overflight on 20 Sep, IGP found the crater of the volcano cold and partly covered with snow. No explosions were observed, different from most previous times in the past 11 years when the remote volcano had been surveyed. The highest temperatures measured in the crater area were about 67°C and the youngest lava flows had temperatures of about 31°C. A large warm zone (part of the summit dome) is located between the central and the northeast crater, which already had been noted during the last overflight in April. The observations made during the overflight seem to indicate a decrease in the activity of Sangay compared to that observed in the last 10 years. This fits well to ground observations from August and September when no explosions were seen or heard from the volcano.
Reventador (Ecuador): Activity has remained unchanged at moderate levels. Weak glow from the summit, intense steaming and few ash explosions occur.
Cotopaxi (Ecuador): IGPEN surveyed the volcano on 20 Sep. Maximum temperatures in the active crater were found at 55.7 °C and no unusual signs of activity or significant morphological changes compared to recent years were observed.
Tungurahua (Ecuador): Activity has been low. During an overflight on 20 Sep, IGPEN staff measured the diameter of the inner crater to be slightly larger (230 m) than compared to August, likely as a result of landslides from its walls. Temperatures at fumaroles inside the crater were relatively low and their activity weak. Low seismic activity and snow inside the crater also suggests that the volcano is currently “sleeping”.
Copahue (Chile/Argentina): The volcano is emitting a weak plume of gas and steam. Minor ash venting could be observed yesterday evening. No glow was visible on night-time webcam images. SERNAGEOMIN has not posted new activity reports.