Semisopochnoi volcano news & activity updates:
Semisopochnoi volcano (Alaska): alert level lowered back to green
Monday Sep 23, 2019 05:55 AM | BY: T
Seismicity at the volcano has decreased over the past few weeks with no observations of seismic tremor since September 15.
Low-level sulfur dioxide emissions continue to be observed when conditions permit. Other than the ongoing refilling of the crater lake, no changes in surface features have been observed since the small, shallow cone that formed around August 24. Due to the decrease in activity, AVO lowered the color code/activity level to YELLOW/ADVISORY on 20 Sep.
Wednesday, Aug 07, 2019
AVO reported that during 31 July-6 August seismicity at the volcano remained elevated and was characterized by periods of weak, continuous tremor and discrete low-frequency earthquakes. Satellite images were mostly cloudy, though a possible steam plume was visible during 5-6 August. ... [more]
Saturday, Jul 06, 2019
Yesterday, the Alaska Volcano Observatory raised the alert level of the volcano due to an increase in seismicity above background levels. ... [more]
Semisopochnoi volcano (United States, Aleutian Islands) activity update: Explosive activity declines, continuing high seismicity
Thursday, Nov 01, 2018
AVO reports that there have been no explosions in the last day, and only two the day before. The volcano remains highly restless and explosions could resume. [more]
Semisopochnoi volcano (United States, Aleutian Islands) activity update: Continuing eruptive activity
Tuesday, Oct 30, 2018
The renewed eruption has continued in the last few days. Regular small explosions are occurring, but there have been no sightings of ash plumes. [more]