If a super-eruption were to occur, the blast would launch enough ash into the atmosphere to disrupt weather for years to follow, potentially causing…

If a super-eruption were to occur, the blast would launch enough ash into the atmosphere to disrupt weather for years to follow, potentially causing famine, health crisis, and global civil unrest

And leading up to the catastrophic event, the world would have just one year to prepare

Researchers have determined this based on a microscopic analysis of quartz crystals in pumice from the Bishop Tuff in California, the site of a super-eruption 760,000 years ago

The ancient super-eruption in eastern California formed the Long Valley Caldera – a feature that is nearly 20 miles long and 11 miles wide

In the study, the researchers from Vanderbilt University and the University of Chicago analyzed dozens of small quartz crystals, remnants from the original underground magma, from the Bishop Tuff

Quartz crystals have distinctive rims, they explain in a paper published to the journal Plos One, and are rich in titanium

Along with this, they are bright in cathodoluminescence, which allowed them to make high-resolution measurements of variation in the titanium, providing detailed insight on the transition from pre-eruptive crystallization to the decompression and crystallization at the time of the blast

This analysis helped to determine rim growth times and growth rates – revealing that these processes largely occurred in a span of less than a year

‘Maximum rim growth times span from approximately 1 minute to 35 years, with a median of approximately 4 days,’ the authors wrote

‘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

’Growth took place under conditions of high supersaturation suggesting that rim growth marks the onset of decompression and the transition from pre-eruptive to syn-eruptive conditions.’

It takes tens of thousands of years for the crust to generate enough eruptible magma, but once formed, these unstable magma bodies only last for centuries to a few millennia

As the decompression occurs, the magma body would likely be expanding as well, having detectable effects at the surface