Posted Monday, Oct. 15, 2012, at 3:02 PM
Photo by Ronaldo Schemidt/AFP/GettyImages.
By studying the Las Cañadas volcanic caldera in the Canary Islands, researchers from the University of Southampton say they now know what triggers violent volcanic explosions: pre-mixing of cooler magma and younger, hotter magma.
In examining crystal cumulate nodules, the researchers determined that the "rims of crystals in the nodules grew from a very different magma, indicating a major mixing event occurred immediately before eruption. Stirring young hot magma into older, cooler magma appears to be a common event before these explosive eruptions."
Researchers chose Las Cañadas because it's produced at least eight significant and violent eruptions during the last 700,000 years.