Research Fellows Directory
Dr Hugh Tuffen
Volcanoes threaten millions of people worldwide, yet our understanding of the processes that control hazardous eruptions remains rudimentary at best. We therefore cannot answer with any certainty simple questions such as when an eruption will start, how violent it will be, or how long it may last. I hope to shed new light on the processes that control volcanic activity, via field observations from current and ancient eruptions, deciphering chemical clues frozen into lava, and conducting experiments at searing magmatic temperatures.
A major aspect of my work is to study enigmatic, infrequent eruptions of highly-viscous rhyolite magma. These are amongst the biggest on Earth and generate huge volumes of pumice, together with immensely thick lavas made of glassy obsidian. Two recent eruptions of rhyolite in Chile, the first to be observed in detail, are yielding unprecedented and unexpected insights about this type of eruption. We have discovered that rhyolite can generate very long-lived ash plumes as particles of sticky magma block up volcanic vents, driving repeated explosions that project ash and bombs skywards at over a hundred metres per second. We have also witnessed obsidian lava moving for the first time, which can relentlessly advance at a fraction of a snail’s pace for many months due to its great viscosity and thickness.
In my lab I heat lava samples to over a thousand degrees, to study the growth of the crystals and bubbles that strongly influence how magma moves. This will assist modelling of lava flowing down volcano flanks. I also map chemical species such as water dissolved within samples of lava to decipher the record of pressure changes within volcanoes prior to explosions, which will help us understand the kind of geophysical signal that may indicate an explosion is imminent.
Finally, I am part of a team that hopes to soon drill into magma within an Icelandic volcano, with the potential to generate the world’s most powerful geothermal energy.
Interests and expertise (Subject groups)