HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Saturday, September 3, 2022, 4:10 PM HST (Sunday, September 4, 2022, 02:10 UTC)
TA'U ISLAND VOLCANO (VNUM #244001)
14°13'48" S 169°27'14" W, Summit Elevation 3054 ft (931 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW
The earthquake swarm related to Taʻū Island continues with no significant change in the past 24 hours. Data shows the earthquake swarm is occurring in a fixed position, but the precise location has been difficult to resolve. Preliminary estimates include a narrow band of possible locations from approximately 30 km (19 mi) beneath the central northern coast of Taʻū Island to an area about 5 km (3 mi) beneath the ocean surface 20 km (13 mi) north of Taʻū Island. Seismologists continue to examine data and refine locations.
In the past 24 hours, the USGS seismic network detected 21 earthquakes that were large enough to be felt by people on the Manuʻa Islands. The largest event of September 2 was a magnitude 3.4. Many small earthquakes undetectable by humans also continue. The American Samoa Emergency Operations Center continues to receive reports of felt earthquakes and booming sounds.
No volcanic activity was observed in available satellite data from the previous 24 hours.
Samoan and English language alert level and color code definitions: (PDF download, 57.68 kb) https://www.usgs.gov/media/files/volcano-aviation-codes-and-alert-levels-english-and-samoan
NEW Web Resource
Read the new Frequently Asked Questions web page for more information. https://www.usgs.gov/observatories/hvo/frequently-asked-questions-about-earthquakes-american-samoa
It is unclear if this earthquake unrest will escalate to a volcanic eruption and exactly where an eruption might occur. An eruption could pose significant hazards to residents of American Samoa; these hazards include volcanic gases, volcanic ash, low-level localized explosions of lava, lava flows, earthquake shaking, and tsunami. Information about these hazards, which are like those in Hawaii, can be found at this HVO website: https://www.usgs.gov/observatories/hvo/hazards.
The primary hazard of concern at this time is earthquake shaking, although no physically damaging earthquakes have occurred as part of this swarm. For information on how to prepare for an earthquake, see: https://www.usgs.gov/faqs/what-can-i-do-be-prepared-earthquake.
If you feel shaking and are not near the coast, immediately drop, cover, and hold on until the shaking stops. If you are at the coast, heed the natural tsunami warning signs. If you feel a strong or long-duration earthquake, see a sudden rise or fall of the ocean, hear a loud roar from the ocean, or see a large aerial plume from an eruption, a tsunami may follow, and you should immediately move to higher ground. Pacific Tsunami Warning Center: https://tsunami.gov/
Volcanoes in the Manuʻa Islands are monitored with a limited real-time seismic network consisting of three sophisticated seismometers —two on Taʻū Island and one on Ofu Island—and six microseismometers on Tutuila, Taʻū, and Ofu-Olosega Islands. Satellite remote sensing is another tool being used, which may detect heat, volcanic gas, and volcanic ash associated with early phases of volcanic activity.
Report what you feel and see.
Residents can assist these monitoring efforts by noting and reporting accurate times that they feel earthquake shaking or notice other changes that might be related to volcanic activity to either the Pago Pago National Weather Service Office (https://www.weather.gov/ppg/wsopagooffice) or the American Samoa EOC in Pago Pago (684-699-3800).
American Samoa Volcanoes
Volcanoes in the U.S. Territory of American Samoa are within the area of responsibility of the U.S. Geological Survey’s Hawaiian Volcano Observatory, based in Hilo on the Island of Hawai‘i.
- Taʻū Island website: https://www.usgs.gov/volcanoes/ta-u-island
- Ofu-Olosega website: https://www.usgs.gov/volcanoes/ofu-olosega
NOAA Weather and Tsunami resources
- National Weather Service Pago Pago Office: https://www.weather.gov/ppg/wsopagooffice
- Pacific Tsunami Warning Center: https://tsunami.gov/
- International Tsunami Information Center and American Samoa Tsunami Awareness Information: http://www.tsunamiwave.org
The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawaiʻi and American Samoa.
HVO, askHVO@usgs.gov—best contact for regular reporting and questions.
Ken Hon, HVO Scientist in Charge, USGS email@example.com
Natalia Deligne, American Samoa Lead Responding Scientist, USGS firstname.lastname@example.org
Subscribe to these messages: https://volcanoes.usgs.gov/vns2/
Summary of volcanic hazards from eruptions: https://www.usgs.gov/observatories/hvo/hazards
Recent earthquakes in Hawaiʻi (map and list): https://www.usgs.gov/observatories/hvo
Volcanoes of American Samoa: https://www.usgs.gov/observatories/hvo/volcanoes-american-samoa
Explanation of Volcano Alert Levels and Aviation Color Codes: https://www.usgs.gov/programs/VHP/volcanic-alert-levels-characterize-conditions-us-volcanoes