Satellite image of Ta’u volcano in the late September (image: Sentinel 2)
The Hawaiian Volcano Observatory (HVO) reported that the seismic activity beneath the volcano rapidly decreased over the past few weeks and continues at low levels.
Therefore, the alert status for the volcano was decreased to „Green“.
HVO scientists use four broadband and eight micro-seismometers to detected earthquakes. The National Earthquake Information Center is monitoring quakes as well, but only greater than M 2.5 in American Samoa. For ground deformation monitoring, two GPS receivers are being used on the Ta’u volcano.
Seismic data during 2005 and 2009 hint that less than five detected earthquakes per day may be the long-term background seismicity rate.
Source: Hawaiian Volcano Observatory volcano activity update 4 October 2022