July in the Manuʻa Islands of American Samoa in the South Pacific. These earthquakes are likely associated with magmatic activity beneath the islands. The USGS Hawaiian Volcano Observatory (HVO) is working closely with federal partners, American Samoan officials, and local residents to better understand the source and potential hazard implications of these ongoing earthquakes.
Volcanoes in American Samoa are similar to those in Hawaii, with the Pacific Plate moving to the northwest over the Samoa hotspot and building submarine volcanoes that eventually emerge from the ocean as islands. These islands are the tops of large basaltic shield volcanoes rising over 15,000 feet (4,500 m) from the surrounding seafloor.
The volcano Kilauea is erupting. (https://www.usgs.gov/natural-hazards/volcano-hazards/about-alert-levels) Its USGS Volcano Alert level is WATCH. Daily Klauea updates are released. Lava has been erupting from Halemaumau crater’s western vent for the past week. The Halemaumau crater in Hawaii Volcanoes National Park is the only place where lava can be found. The most recent estimate of sulphur dioxide emission rates was 1,150 tonnes per day (t/d) on August 12. These rates are quite high. Although there are few earthquakes and ongoing volcanic tremor, seismic activity is high yet stable. Summit tiltmeters captured a number of deflation-inflation occurrences over the previous week (DI-events). Visit https://www.usgs.gov/volcanoes/kilauea/recent-eruption for additional details on Klauea’s ongoing eruption.
While Mauna Loa is still at Volcano Alert Level ADVISORY, it is not currently erupting. This alert level does not indicate that an eruption is imminent or that the passage from the current state of unrest to an eruption is inevitable. Weekly updates on Mauna Loa are released.
The majority of the 96 small-magnitude earthquakes that occurred this past week occurred at shallow depths of less than 15 kilometres (9 miles) beneath the summit and upper elevation slopes of Mauna Loa. Low rates of ground deformation have been observed during the past week, according to GPS measurements. The Southwest Rift Zone’s summit and Sulphur Cone both exhibit constant gas concentrations and fumarole temperatures throughout the past week. The scenery hasn’t changed, according to webcams.
