Kilauea scientists study exposed volcanic layers to trace eruptive history

Scientists from the USGS Hawaiian Volcano Observatory (HVO) are utilizing newly exposed geological layers to study the long-term eruptive history of Kilauea. In July, researchers visited exposures of tephra and lava flows located in the western wall of Kaluapele.

These layers were revealed following a 1,640-foot (500-meter) deep summit caldera collapse in 2018. This event, described as a ‘hulihia’ or dramatic change, exposed volcanic deposits that had not been visible at Kilauea since the HVO was founded in 1912. Because Kilauea is frequently active, much of the volcano is obscured by lava flows less than 1,000 years old, making these deep exposures critical for studying the volcano’s shield-building stage, which has lasted over 200,000 years.

To analyze the site, geologists used uncrewed aircraft systems (drones) to create high-resolution photographic mosaics of the caldera cliffs. Since 2023, HVO geologists have been conducting missions to these newly exposed sections to gain insights into the volcano’s evolution and catalog some of the oldest eruptions recorded near the summit.