High ambitions

A world-renowned Irish expert in volcanic activity can now bring some of his work closer to home, writes Rebecca Knowles.

A world-renowned Irish expert in volcanic activity can now bring some of his work closer to home, writes Rebecca Knowles.

While not traditionally a "hot" topic in Ireland, the study of volcanoes by scientists here is getting a welcome boost from an Irish expert in the field, Prof John Gamble.

Prof Gamble, a 1974 graduate of Queen's University, worked for years in Australia and New Zealand before returning to Ireland in 2002 to take up his current position as University College Cork's chair of geology.

Along the way he was airlifted to remote locations in Antarctica for seven separate deep field research seasons, each lasting several months. His contributions to Antarctic geoscience were recognised with the naming of the Gamble Glacier in the Trans Antarctic Mountains, and Gamble Cone on Ross Island, just off the coast of Antarctica.

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People tend not to think of Antarctica as volcano territory, Prof Gamble says, "but there is an active rift region, it's just under thousands of metres of ice".

Most recently, his work has focused on the inner workings of active andesite volcanoes, in particular those of Mt Ruapehu, the highest mountain on New Zealand's North Island and most active of the country's on-shore volcanoes.

In the interest of improving future predictions of activity, Prof Gamble detailed lava flows over the millenniums, from pre-historic times to the present and in the process learning as much as possible about fluctuations of magmas.

"We are trying to understand the dynamics of the volcanoes' plumbing systems and how magma evolves on its way to the surface, which is what actually gives rise to very big explosions," Prof Gamble explains.

"One of the major questions is how rapidly do the magmatic systems re-prime themselves."

It was his research into subduction zone volcanism - where volcanoes occur when one piece of the Earth's crust slides under another - that made Prof Gamble the namesake of yet another geological site, the Gamble Volcanic Complex. This is a chain of active submarine volcanoes located on the Kermadec Arc, just north of New Zealand.

Subduction zones foster earthquakes and volcanoes, with associated volcanic activity often likely to be both highly explosive and difficult to predict.

At least a quarter of the world's population lives close to a subduction zone volcano - including volcanoes found along the Pacific Ring of Fire - so research and observation towards better prediction of volcanic activity is all the more critical, he believes.

Now, thanks in part to funding from Science Foundation Ireland's Research Frontiers Programme, some of the same analysis work Prof Gamble was, by virtue of necessity, accustomed to doing overseas, can instead be carried out in Ireland. A consortium of interested geological scientists has formed, and the group recently made a major equipment purchase.

"Ireland hasn't got a great infrastructure for research in the area I work in, but that has changed some in the past two years," Prof Gamble says.

"Now we'll have a mass spectrometer and laser system in Dublin that will allow us to determine ages of rocks and to measure with high precision certain geological tracers; not just deep rocks but also surface processes, so it should also be useful to people interested in areas like climate change."

THE SFI FUNDING also supports related research by PhD scholars Mairi Gardner and Cora McKenna. Gardner is comparing eruptions from New Zealand volcanoes with those from Anak Krakatau in Indonesia, while McKenna is examining flood basalts - rocks formed as a result of massive lava eruptions that blanket vast expanses of land - in northeast Ireland.

Although Prof Gamble is already five years removed from his post as head of the department of geology at Victoria University in Wellington, New Zealand, his research contributions to understanding volcanism in the southwest Pacific are still reverberating among his contemporaries there.

A symposium in his honour formed part of the annual meeting of the Geological Society of New Zealand and the New Zealand Geophysical Society, held last November in Tauranga.

"He is regarded as an authority on the Tonga-Kermadec-New Zealand volcano chain, and has inspired a whole generation of colleagues and students, many of whom came to the Tauranga conference," says Nick Mortimer, president of the Geological Society of New Zealand.