Experts unclear source of earthquakes around Manu’a islands


To date, it is unclear where the earthquakes are coming from around the Manu’a Islands. For the last week, residents of the Manuʻa group of islands in American Samoa continue to feel earthquakes.

The US Geological Survey Hawaiian Volcano Observatory (HVO) in its latest report says that Taʻu residents suggest that the activity began on July 26. “Since August 10, earthquakes have also been reported by residents of Ofu and Olosega islands,” according to the report.

These reports suggest that the earthquakes vary in intensity, but are generally short, sharp jolts. “The earthquakes are more likely to be felt by people indoors at rest and along the coast, where buildings sit on sediment that amplifies shaking. These factors are probably responsible for the variability in reporting.

“Based on the reports, these earthquakes are probably related to either Taʻū or Vailuluʻu volcanoes.”

On Friday some residents in Manu’a called on the American Samoa Government to evacuate them, and on Saturday a chartered flight took Emergency Operations Center personnel to Manu’a. Dr Natalia Deligne of the US Geological Survey Hawaiian Volcano Observatory (HVO), arrived in Pago Pago on August 11 and is consulting with territorial authorities.


Last week the American Samoa Government Manu’a moved to evacuate people from Manu’a. 

In the meantime, the The Samoa Government has activated the National Emergency Operation Center to monitor very closely, the Vailuuluu underwater volcano situation.

“Vailulu’u is a conical seamount, the youngest and easternmost volcano in the Samoan Archipelago.

“This underwater volcano was discovered active in 2017 by an American Samoa Expedition of the National Oceanic and Atmospheric Administration (NOAA).

“The Samoa Meteorology Office is monitoring closely a continuing earthquake swarm occurring in the Manuʻa islands of American Samoa.”

The statement issued yesterday by the NEOC says this cluster of earthquakes is most likely related to Vailu’ulu’u seamount and/or the nearby submarine volcanoes in the American Samoa region.