AVO Semisopochnoi ORANGE/WATCH – Seismic unrest continues; no ash emissions detected

Aug 9, 2019 23:04 – Seismic activity remained elevated throughout the week with periods of continuous tremor and low-frequency earthquakes. Other than an increase in seismicity on Tuesday, August 6, there has been a general decrease in seismic activity over the past week. Semisopochnoi has been obscured by clouds for most of the week and no unusual activity has been observed in satellite views. There are no definitive indicators of lava in the crater at this time.

Semisopochnoi is monitored with an on-island seismic network and remotely by satellite and lightning sensors. Furthermore, an …