Seismic surveys have challenged the long-held notion that only active volcanoes harbor large magma bodies beneath them. A team of researchers used seismic waves to investigate six volcanoes in the Cascade Range, discovering that even dormant ones possess persistent and substantial magma chambers.
The study’s findings are surprising, given that some volcanoes, like Crater Lake volcano in Oregon, have been inactive for millennia. However, Guanning Pang, a postdoctoral researcher at New Cornell University, explains that large magma bodies exist beneath volcanoes throughout their entire lifetime, not just during periods of activity.
This discovery has significant implications for monitoring and predicting future volcanic activity. Researchers are now reassessing the notion that large magma bodies necessarily signal increased likelihood of eruption. Instead, it appears that an eruption releases excess volume and pressure, allowing the chamber to refill over time.
The U.S. Geological Survey is upgrading its volcanic monitoring networks in the Cascade Range as part of the National Volcano Early Warning System. Plans are underway to expand a new magma monitoring system, with potential applications to other locations like Alaska.
With over 800 million people living within 60 miles of an active volcano, optimizing monitoring efforts is crucial. The study’s findings highlight the importance of detecting signals of impending eruptions as early as possible, given that more than 278,000 lives have been lost in volcanic eruptions over the past 500 years.
Source: https://www.forbes.com/sites/davidbressan/2025/01/30/even-sleeping-volcanoes-have-large-magma-bodies-sitting-beneath-them