The level of volcanic activity has remained the same overnight. There have been two swarms of volcano-tectonic earthquakes. The first swarm started at 5:50 pm and lasted for over three hours, with 48 earthquakes recorded. This is slightly larger and longer than other recent swarms. The swarm was followed by a group of five long-period earthquakes, and a few rockfall signals. The second swarm started at 5:40 am, and is on-going.
The volcano is cloudy, and so no observations have been possible this morning. Yesterday, continued dome growth was observed within the scar caused by the dome collapse on Monday evening. This new extrusion was described by one of the scientists as one of the most impressive sights he has seen during this eruption. The extrusion rate seems to be high just now, and it is expected that further collapses will occur in the next few days.
If a major dome collapse happens, it would probably build up over a period of several hours, and could produce large pyroclastic flows in the Tar River valley and heavy ash fall downwind of the volcano. Should the collapse be very large, then an explosive eruption is possible, in the same way that it followed a major dome collapse on September 17/18. At the moment the scientists are confident that zone E, which includes Corkhill and the airport, remains safe. The Tar River area is extremely dangerous, and should not be entered in any circumstances.