Pumice Raft “Vitamin Shot” for Australia’s Great Barrier Reef

A giant raft of pumice is helping to sustain Australia’s Great Barrier Reef.

The pumice was the result of an underwater volcano which erupted near Tonga in 2019.

Pumice is a lightweight bubble-rich rock that can float in water and forms when frothy magma cools rapidly. The giant raft floating from the area it was formed in has arrived on Australia’s shoreline, 3,000Km away from where it started.

Associate Professor Scott Bryan described it as “like a vitamin shot for the Great Barrier Reef.”

Professor Bryan recovering pumice from the Tonga August 2019 eruption. Credit QUT

Professor Bryan described the process of the pumice raft boosting the Great Barrier Reef as part of a “very ancient process” in which oceans and volcanoes have likely combined to transfer marine life around the Earth for hundreds of millions of years.

“This shows that the Great Barrier Reef has connections to coral reefs that are thousands of kilometres further east.”

The underwater volcano and the eruption site near Tonga was explored using robotics by a team including Professor Bryan and Professor Matt Dunbabin of  QUT’s (Queens University of Technology) Centre for Robotics.

This meant the scientists could take samples from the area and the sea floor soon after the eruption. Satellite images were also used to follow the pumice raft.

Attached to the pumice raft are marine organisms.

Professor Scott Bryan recovering pumice. Credit QUT

Professor Bryan said:

“Overall, we’ve identified more than one hundred different species attached to the pumice – a tremendous diversity of plants and animals.

“Each piece of pumice is a home, and a vehicle for an organism, and it’s just tremendous. The sheer numbers of individuals and this diversity of species is being transported thousands of kilometres in only a matter of months is really quite phenomenal.”

Link: Defining Pre-eruptive Conditions of the Havre 2012 Submarine Rhyolite Eruption Using Crystal Archives

Reporter: Fiona Grahame

Leave a Reply