Super-eruptions are years in the making. First, magma from the mantle rises, collects and pushes up against the crust. As it accumulates but is unable to break through, pressure builds. This process occurs on a large timescale, but researchers have identified a predictive process occurring on a smaller timescale -- rim growth.
Researchers were able to use the amount of titanium accumulated in quartz crystals to measure a volcano's rim growth over time. Maximum rim growth corresponds with decompression, the release of pressurized gas that powers a super-eruption -- the beginning of the end.
"Maximum rim growth times span from approximately 1 minute to 35 years, with a median of approximately 4 days," researchers wrote in their new paper on the subject. "More than 70 percent of rim growth times are less than 1 year, showing that quartz rims have mostly grown in the days to months prior to eruption."
