When a volcano shows signs of unrest, scientists face a critical question: Will it erupt, or will the magma stop underground? The answer can determine whether thousands of people need to evacuate their homes.
Jiaxuan Li, assistant professor of geophysics and seismology in the University of Houston College of Natural Sciences and Mathematics (NSM), has received a $301,030 grant from the U.S. National Science Foundation to advance technology that uses existing fiber-optic telecommunications cables to monitor underground magma movement in near real time.
Li leads the three-year collaborative project, which aims to improve eruption forecasting, helping scientists and emergency officials make more informed decisions when volcanic activity threatens communities.
Why Some Volcanoes Erupt and Others Do Not
Li鈥檚 research focuses on Iceland鈥檚 Reykjanes Peninsula, where volcanic activity has forced the evacuation of the town of Grindav铆k and threatened critical infrastructure.
鈥淲hen magma starts moving toward the surface, why does it sometimes erupt and sometimes stall underground?鈥� Li said. 鈥淚n our first year of recording on Iceland鈥檚 Reykjanes Peninsula, there were nine magma intrusions near the town of Grindav铆k. Six erupted. Three stopped short.鈥�
Predicting which intrusions will erupt is difficult because the deciding processes can unfold several kilometers beneath Earth鈥檚 surface in a matter of minutes or hours. Traditional monitoring tools, including GPS and satellites, cannot always capture these rapid changes.
Li鈥檚 approach uses a technology called distributed acoustic sensing, which transforms existing fiber-optic cables into networks of highly sensitive ground sensors.
By sending laser pulses through the cables, researchers can detect tiny movements in the surrounding ground. In Iceland, one 100-kilometer cable effectively became approximately 10,000 sensors, allowing scientists to monitor underground activity with high resolution in both space and time.
鈥淲ith that, we can track a magma-filled crack as it opens underground, minute by minute instead of day by day,鈥� Li said.
The technology has already demonstrated promising results. According to Li, the system detected two small magma intrusions in 2024 that GPS and satellite measurements missed. It also generated an automatic alert 26 minutes before an August 2024 eruption and provided more than two hours of warning before the April 2025 eruption.
A Collaborative Approach
Building on monitoring efforts that began in 2023, Li鈥檚 UH research group leads the fiber-optic monitoring and modeling efforts, working alongside Zhongwen Zhan鈥檚 group at the California Institute of Technology and researchers at the Icelandic Meteorological Office.
The team will combine fiber-optic measurements with satellite data, GPS observations and seismic imaging to better understand why some magma intrusions lead to eruptions while others stop underground.
The NSF award will also support a UH graduate student and a postdoctoral researcher, expanding opportunities for hands-on research with international applications.
Bringing the Technology to U.S. Volcanoes
Although the research centers on Iceland, its potential benefits extend to volcanic regions across the United States.
Fiber-optic cables already run near many active volcanoes and across the seafloor, offering opportunities to strengthen monitoring without installing entirely new sensor networks.
鈥淚n the U.S., fiber already runs near many active volcanoes and across the seafloor, so the same approach could work without building new monitoring networks,鈥� Li said.
The researchers plan to make their software publicly available, allowing scientists to explore applications at K墨lauea in Hawaii, Mount Spurr in Alaska, Yellowstone and Axial Seamount off the Oregon coast.
For Li, the ultimate goal is to give scientists and emergency officials better information when communities face the threat of an eruption.
鈥淎 missed eruption puts lives at risk, and a false alarm empties a town for nothing,鈥� Li said.
By turning existing infrastructure into a powerful scientific monitoring tool, the NSF-funded research could help communities prepare for volcanic hazards with greater confidence and more time to respond.