Images

Two USGS scientists service a seismic station on Tutuila island in American Samoa. The Hawaiian Volcano Observatory uses this site and three others to monitor volcanic activity in American Samoa. These stations are also used by the NOAA Pacific Tsunami Warning Center and the USGS National Earthquake Information Center. USGS photo by N. Deligne.

This photo, taken from an airplane, shows Aunu‘u Island from the south looking north; Tutuila Island is visible on the left. Aunu‘u Island is a tuff cone less than 1 mile southeast of Tutuila Island and is considered part of Tutuila volcano. A tuff cone can form when magma and water interact at shallow depths, causing localized explosions.

USGS Hawaiian Volcano Observatory scientists took this photo of Aunu‘u Island while on a flight from Tutuila to Ofu Island in American Samoa on September 2, 2025. The view is from the south looking north. Aunu‘u Island is a tuff cone less than 1 mile southeast of Tutuila Island and is considered part of Tutuila volcano.

A view to the west across Pago Pago harbor at Matafao Peak on Tutuila Island, American Samoa. Matafao Peak is the highest part of Tutuila Island at an elevation of 2,142 feet (653 meters) above sea level. It is part of the Matafao Peak National Natural Landmark. USGS photo by D. Downs.

A view of Rainmaker Mountain to the east of Pago Pago harbor on Tutuila Island, American Samoa. Rainmaker Mountain was mapped in the 1940s as a trachyte plug by geologist Harold Stearns. Dense jungle, the highest annual rainfall in American Samoa, and its steep cliffs make it a formidable mountain to summit. USGS photo by D. Downs.

A view looking at the basalt lava flows that make cliffs along the southwestern part of Tutuila Island, American Samoa. These flows are part of the Leone volcanic series and form the flattest part of Tutuila Island, where the airport and population center of Tafuna are located. USGS photo by D. Downs.

The view looks south along the basalt cliffs and beaches at Tula point on the eastern end of Tutuila Island, American Samoa. Tutuila Island is a shield volcano, formed by basalt flows that are 1-1.5 million years old.

Map of the American Samoa volcano-monitoring network (top). Data from Wake Island hydrograph (located about 4,500 km, or 2,900 miles, northwest of Taʻū Island) shows the general trend in the number of events during the 2022 earthquake swarm (bottom left). Locations for larger earthquakes (M2.5 and greater) are available starting August 20, 2022 (bottom right).

Bathymetric data from the National Oceanic and Atmospheric Administration (NOAA) collected around American Samoa. Light gray areas are the islands of Tutuila, Ofu-Olosega, and Taʻū. Black lines are 1,640 ft (500 m) contour intervals below sea level.

A USGS scientist installs a seismic station on Tutuila island in American Samoa. This station joins several other stations recently installed in the Manu‘a Islands to monitor activity in American Samoa. USGS photo by A. Ellis.

This reference map depicts the topography and bathymetry of the volcanoes in the Manu‘a Islands, American Samoa. The highest elevation in the area is Lata Mountain on Ta‘ū Island, standing 3,179 feet (969 meters) above sea level.

This reference map depicts the volcanic islands of American Samoa, and specifically the Manu‘a Islands of Ofu, Olosega, and Ta‘ū. In recent days and weeks, residents of the islands have been feeling moderate earthquakes, and the Hawaiian Volcano Observatory has deployed several staff members to American Samoa to help monitor the unrest.

NASA Astronaut image of Tutuila island (Manu'a Islands, American Samoa) in the South Pacific Ocean. NASA - ISS002-701-263.