Nearly three years after Kilauea Volcano started spewing lava within the Leilani Estates subdivision in Lower Puna, the historic eruption of 2018 continues to fuel scientific study.

A team of researchers, including University of Hawaii at Manoa School of Ocean and Earth Science and Technology Professor Bruce Houghton and Brian Shiro of the U.S. Geological Survey’s Hawaiian Volcano Observatory, identified an indicator of magma viscosity that can be measured prior to an eruption, providing critical information on how the eruption will play out, according to a news release.

Understanding the possible patterns of impending eruptions could help scientists and emergency managers determine the hazard potential for nearby communities, the release said.

“The study is very unusual because it falls at the interface between two distinct disciplines in volcanology: seismology and studies of the viscosity (fluidity) of the molten rock,” Houghton said in the release.

Their findings were published today in the journal Nature.

Highly viscous magma, which is thick and sticky, can block gas from escaping through vents, allowing pressure to build up inside a volcano’s plumbing system and resulting in powerful explosions. Extrusion of more viscous magma also results in slower-moving lava flows.

“But magma viscosity is usually only quantified well after an eruption, not in advance,” said Diana Roman, lead author of the study and volcanologist at Carnegie Institution for Science in Washington, D.C., in the release. “So, we are always trying to identify early indications of magma viscosity that could help forecast a volcano’s eruption style.”

The three-month-long eruption in 2018, which destroyed more than 700 homes, provided “a wealth of simultaneous data about the behavior of both high- and low-viscosity magma, as well as about the pre-eruption stresses in the solid rock underlying Kilauea,” the release said. As the volcanic activity caused faults — fractures in the rock that makes up the Earth’s crust — to move against each other, scientists used seismic instruments to measure their 3-D orientation and movement.

They were able to determine that the direction of the fault movements in the lower East Rift Zone before and during the eruption could be used to estimate the viscosity of rising magma.

“We were able to show that with robust monitoring we can relate pressure and stress in a volcano’s plumbing system to the underground movement of more viscous magma,” Roman said. “This will enable monitoring experts to better anticipate the eruption behavior of volcanoes like Kilauea and to tailor response strategies in advance.”

Other researchers in the study were Arianna Soldati and Don Dingwell of Ludwig-Maximilians-University of Munich.