Scientists Capture First 3D Images of Mexico’s Popocatépetl Volcano

A team of scientists from Mexico’s National Autonomous University has successfully created the first three-dimensional images of the interior of the Popocatépetl volcano, which stands at 17,883 feet (5,452 meters) and is among the world’s most active volcanoes. This groundbreaking achievement aims to enhance understanding of the volcanic activity and assist authorities in responding to potential eruptions that could impact millions living in proximity to the volcano.

The research team, led by Marco Calò, a professor in the UNAM’s Geophysics Institute, has spent five years hiking the slopes of Popocatépetl, carrying heavy equipment despite the risks of adverse weather and volcanic explosions. Their mission has focused on uncovering the dynamics occurring beneath the crater, which could have significant implications for safety and preparedness in the region.

Mapping the Volcano’s Interior

Inside an active volcano, various elements such as rocks, magma, gas, and aquifers constantly shift, generating seismic signals. While many dangerous volcanoes around the globe have detailed interior maps, Popocatépetl had been lacking such comprehensive data until now. Approximately 25 million people reside within a 62-mile (100 kilometers) radius of the volcano, which poses a serious risk to infrastructure, including homes, schools, hospitals, and airports.

Previous attempts to image the volcano’s interior were made around 15 years ago, but those efforts produced inconclusive results and lacked the resolution necessary to adequately assess magma accumulation. In response, Calò’s team expanded the number of seismographs from 12 to 22 around the volcano’s perimeter. Although only three instruments are needed to trigger emergency alerts, a more extensive network enhances the understanding of seismic activity.

The scientists have employed advanced artificial intelligence techniques to analyze seismic data collected from these instruments, allowing them to catalog various types of tremors and infer the characteristics of materials beneath the surface, such as temperature and depth.

A Deeper Understanding of Volcanic Activity

The resulting three-dimensional cross-section of the volcano extends 11 miles (18 kilometers) below the crater and reveals multiple magma pools at varying depths, with dense material found primarily in the southeastern region. This intricate view contradicts the simplistic diagrams of volcanoes often seen in educational settings, offering a more complex understanding of Popocatépetl’s structure and behavior.

Known affectionately as “El Popo” by locals, the volcano has been active since 1994, regularly emitting smoke, gas, and ash. Its eruptions periodically create a dome over the main vent, which eventually collapses, leading to explosive activity. The most recent eruption occurred in 2023.

Calò, originally from Sicily, expressed his enthusiasm for the volcano, noting its historical significance and the profound impact it has had on surrounding communities. He recounted how human activities in the early 20th century, such as dynamite use for sulfur extraction, inadvertently triggered eruptions. Despite Popocatépetl’s substantial greenhouse gas emissions, they remain a fraction of the pollution generated by nearby Mexico City.

The team’s hands-on approach marks a departure from Calò’s previous work, where he analyzed volcanic activity remotely. His experience with Popocatépetl has offered valuable insights into the volcano’s behavior, which he describes as “majestic.”

As the scientists camped at approximately 12,500 feet (3,810 meters) above sea level, they set up equipment in a grove of trees, strategically chosen for safety from potential pyroclastic flows. The expedition provided breathtaking views and a unique auditory experience, with echoes of the volcano’s sounds resonating at night.

During their research, the team encountered challenges, including damaged equipment and the effects of natural elements. However, their determination to map the volcano’s interior remains steadfast. Each expedition yields new data, contributing to a more comprehensive understanding of Popocatépetl’s dynamics and potential hazards.

Calò emphasized the importance of providing residents with reliable information about the volcano’s behavior, which is crucial for effective emergency preparedness. The team’s innovative use of technology and dedication to their research will likely inform future protocols and responses to volcanic activity in the region.

As the final expedition before the publication of their findings approaches, the team reflects on the journey. For many, including doctoral student Karina Bernal and master’s student Karina Rodríguez, the ability to visualize the volcano’s interior in three dimensions is a source of inspiration and motivation to continue their work in this natural laboratory.