Volcano Information

    Ahyi
    Volcanic Alert Level: UNASSIGNED Aviation Color Code: UNASSIGNED

    • Volcanic History Overview: Ahyi seamount is a large conical submarine volcano that rises to within 137 m of the sea surface about 18 km SE of the island of Farallon de Pajaros (Uracas) in the northern Marianas. Water discoloration has been observed over the submarine volcano, and in 1979 the crew of a fishing boat felt shocks over the summit area of the seamount followed by upwelling of sulfur-bearing water. On April 24-25, 2001 an explosive submarine eruption was detected seismically from a seismic station on Rangiroa Atoll, Tuamotu Archipelago. The event was well constrained (+/- 15 km) at a location near the southern base of Ahyi; the summit of the seamount lies within the location uncertainty. From the Smithsonian Global Volcanism Program.
    • Location: Mariana Islands, Mariana Islands

      Latitude: 20.42
      Longitude: 145.03
      Elevation: -137 m

      Recent Eruption: 2001
    • Hazard Assessments: Sako, M. K.; Trusdell, F. A.; Koyanagi, R. Y.; Kojima, George; Moore, R. B., 1995, Volcanic investigations in the Commonwealth of the Northern Mariana Islands, April to May 1994, USGS Open-File Report 94-705.
    • Link to monitoring data: NMI Web Site