Geological Sciences

Geological Sciences

Magma brewery to help predict volcanic eruptions


Ben Kennedy (left) and Felix Von Aulock.

13 September 2012

University of Canterbury volcanologists have invented a very expensive super alloy pressure cooker that will help GNS Science better predict volcanic eruptions.

The cooker, a magma brewery, is the brainchild of senior lecturer Dr Ben Kennedy (Geological Sciences) and PhD student Felix Von Aulock.

"It is the first of its kind in New Zealand and better than others that exist elsewhere in the world," said Dr Kennedy.

"We are a country with a number of active volcanoes and this will significantly help in our research to understand their activity better. We like to know what magma is doing under the crater. Is there any magma? Is the magma rising? Are bubbles growing in the magma? These are the questions that our magma brewery can help with.

"Magma plugs, similar to corks in champagne bottles, allow pressure to build up in volcanoes. The bubble and gas content are the critical magma properties that control volcano explosivity. However, how these properties develop as the magma solidifies or re-melts remains poorly understood."

The volcano testing machine was built by an independent engineer Pete Jones in collaboration with UC's engineering department.

The state of the art high temperature pressure vessel is being used to investigate changes in properties and pressure in rocks from volcanic plugs. The results will be invaluable to hazard mitigation and eruption modelling for volcanic eruptions in New Zealand.

Dr Kennedy said they should be producing data in the next few weeks and carry out ongoing research in the coming years that will be helpful to GNS Science to better predict eruptions.

"The magma we heat gets up to 750 degrees Celsius and we open valves very carefully to release the pressure enough to grow bubbles without explosion, a bit like slowly opening a coke bottle. We do everything up to the point of an explosion.

"We have samples from our magma brewery and from White Island that we then explode in Munich, Germany, on a similar machine. We hope to get samples from Tongariro as soon as it is safe to go up there. It’s really ground-breaking stuff."

Dr Kennedy is studying the Tongariro eruption of 6 August with UC's Dr Tom Wilson (Geological Sciences).

"The ash from that eruption was the most electrically conductive they had ever seen, so it would be really nice to produce some in the lab," Dr Wilson said.

"Given the thickness of ash which fell on the power lines, it must have come close to causing a flashover (short circuit)."
 

For further information please contact:
Kip Brook
Media Consultant
Communications and External Relations
University of Canterbury 
Ph: + 64 3 364 3325
Mobile: 027 503 0168
kip.brook@canterbury.ac.nz