Unnamed Volcano

Tonga Islands - NW of Tongatapu Island


SUMMARY

Type: submarine vent
Activity: active
Last Eruption: 1999
Rock Type: ?
Eruptive Volume: ?
Location Map from Xerox PARC
Latitude: 20.86 S
Longitude: 175.54 W


Geologic Background:

This large sumarine stratovolcano rises to near the ocean surface from a submarine ridge segment trending NNE towards Falcon Island. A shoal has existed at the site during historical times that has been measured at a depth of about 13 m.

Historic Activity:

  • Submarine activity was reported during August 1911 and July 1923. The 1923 activity included a steam column that rose about 30 m above sea level. In January 1970 a large area of water discoloration was observed either at this location or at Falcon Island.

Recent Activity:

  • Submarine activity was reported from January 8 to January 12, 1999. Reports described a vent producing an ash-and-steam column and ejecting lava fragments, and floating pumice near the eruption site.

Data Sources:

  • Global Volcanism Network Bulletin (V. 24, No. 3).

ADDITIONAL INFORMATION


Last Update: 12/15/00