A recent study from the California Institute of Technology (CIT) has shed light on the Long Valley Caldera in eastern California, revealing that it is cooling down rather than heating up, easing concerns about a supervolcanic eruption. The Long Valley Caldera’s last major eruption occurred about 100,000 years ago when it buried the area under a kilometre of sediment, including what is now Los Angeles.
In recent decades, the caldera has experienced periods of “pronounced unrest” marked by seismic activity and ground deformation. However, researchers at CIT suggest that this is due to the supervolcano cooling off rather than preparing for an eruption. The cooling process may release gas and liquid, leading to earthquakes and minor eruptions.
The study utilized data from a 100-kilometre fibre optic cable with distributed acoustic sensing, equivalent to 10,000 individual seismometers. Over 2,000 seismic events were catalogued over a year and a half and analyzed using a machine learning algorithm to create high-resolution maps of the caldera and the underlying volcano.