Tongan Ring Of Fire

An underwater volcanic eruption has spewed out smoke and gas high into the sky creating a new island in the Pacific Ocean about 7 miles off the coast of Tongatapu, the main island of Tonga. This can be located to the southeast of Fiji and about 3000km off the eastern coast of Australia.

The conditions for the creation of pumice are easily met: high pressure lava (molten rock) ejected through low pressure water causing rapid cooling and the consequential formation of bubbles in the liquid. There is satellite picture-evidence of a huge raft of pumice floating about two miles north of the eruption. An earthquake (7.7 magnitude) caused the Pacific Tsunami Warning Center (website) to issue a warning:

19th March 2009 19:31
Tonga Islands Region
Fixed Regional Warning Supplement
Pacific

• Sea level readings confirm that a tsunami was generated. This tsunami may have been destructive along coastlines of the region near the earthquake epicentre. Authorities in the region should take appropriate action in response to this possibility. This center [sic] will continue to monitor sea level gauges nearest the region and report if any additional tsunami wave activity. The warning will not expand to other areas of the Pacific unless additional data are received to warrant such an expansion.

Hawaii (5000km distant) was potentially threatened, but the warning was later officially cancelled.