- Current Update, last updated May 2, 2014 09:52 :
The submarine activity that began on 24 April ChST (23 April UTC), and was detected by seismic stations on Pagan, Sarigan, Anatahan and Saipan is continuing. The location of the unrest has not been confirmed, but available data indicates that a likely source of the seismic activity is at or near Ahyi seamount. Since we are unable to precisely locate the source of the activity, it is possible that the vent is one of the other volcanic seamounts in the area.
Seismic activity has changed little over the past week. Satellite images show nothing out of the ordinary and we have received no reports of activity at the ocean's surface.
- 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
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
Volcanic Alert Level: ADVISORY Aviation Color Code: YELLOW