Volcanoes of the United States

Ahyi, United States

Submarine volcano · -75 m (-246 ft) · Mariana Is-C Pacific

Ahyi is a submarine volcano in the United States, -75 m (-246 ft) high. Its last known eruption: undated, but a probable Holocene eruption. NOAA records no significant eruption here.

Ahyi on the map

Ahyi and the volcanoes within 300 km, colored by when each last erupted.

  • Since 1964
  • 1900 to 1963
  • 1800s
  • AD 1 to 1799
  • Before AD 1, or undated

Open the live map with volcanic ash advisories

Now

From the USGS Volcano Hazards Program, read 15:32 UTC. USGS threat ranking: Very Low Threat.

Advisory / Yellow USGS, Northern Mariana Islands rates Ahyi at alert level Advisory, aviation color code Yellow, since 2026-09-18 00:41 UTC.

NMI Ahyi Seamount YELLOW/ADVISORY - No plumes seen in satellite images; no significant geophysical signals.

Notices this week

  • 2026-09-18 00:41 UTC: Weekly Update, USGS, Northern Mariana Islands

The latest noticeThe observatory’s page

The volcano

Type
Submarine volcano
Elevation
-75 m (-246 ft)
Region
Mariana Is-C Pacific
Summit
20.420° N, 145.030° E
Last known eruption
Undated, but a probable Holocene eruption
Holocene activity known from
Uncertain
Smithsonian volcano number
284141

Significant eruptions

NOAA records eruptions that killed, did damage, were very large, or set off a tsunami or earthquake.

None on record.

Around it

The volcanoes within 300 km.

Earthquakes near AhyiVolcanic ash advisories on the live map

Sources

Volcanoes and significant eruptions from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-09-24. Alert levels, color codes and notices from the USGS Volcano Hazards Program and its observatories, public domain. Volcano numbers are the Smithsonian Institution’s Global Volcanism Program’s.