Author: Stephen Pincock
Source: ABC Science 
July 20, 2012
"Thousands of kilometres of ocean may separate Tonga's many volcanoes and Australia's iconic Great Barrier Reef, but researchers have found an interesting connection.
The unexpected connection is pumice, a lightweight, frothy rock that forms when molten lava cools rapidly in the air or ocean, explained geologist Dr Scott Bryan from the Queensland University of Technology.
The eruption of Tonga's Home Reef volcano in 2006, for example, left billions of pieces of pumice floating on the ocean, initially covering an area of at least 440 square kilometres."
To read the full text of this article, click here .