A giant raft of rocks that has been floating across the Pacific Ocean has started to arrive in Australia.
The vast floating mass of rocks, called pumice, was first spotted in August last year, and covers the water surface for about 150 square kilometres. Researchers say the rocks are carrying organisms that might give Australia’s Great Barrier Reef, the largest coral reef in the world, a much-needed boost.
The floating pumice came from the eruption of an underwater volcano in Tonga, a group of islands more than 2,000 miles away. When underwater volcanoes erupt, the magma (very hot, melted rock) that comes out of the volcano cools in the water, and hardens quickly, trapping gas bubbles inside. These holes make the pumice light enough to float.
As it travels, the…
