Five years after the 2018 Kilauea eruption, a new research project on the volcano will develop the most accurate model yet of its inner workings.
Following the eruption — which began exactly five years ago today and destroyed more than 700 homes and other structures in lower Puna over four months — the U.S. Geological Survey’s Hawaiian Volcano Observatory in 2019 received funding to expand and improve its monitoring systems surrounding the volcano.
That effort will come to fruition this month, said HVO geologist Matt Patrick.
Patrick said researchers have placed 1,800 miniature seismometers around Kilauea’s summit region which will collect various seismic signals throughout May.
Some of those signals will be natural, but others will be artificial, Patrick said.
A piece of equipment called a Vibroseis truck will begin operating around Kilauea next week. The vehicle generates vibrations at specific, controlled frequencies that can be detected by the seismometers and synthesized into a model of Kilauea’s inner structures.
“It’s sort of like a CT scan for the magma chamber,” Patrick said, adding that the new model should be the clearest yet of how the volcano operates.
Because of that, the Vibroseis project will help forecast Kilauea’s future volcanic activity.
Patrick, who was working in the field for HVO throughout the 2018 eruption, said the eruption had provided the clearest picture so far of Kilauea’s magmatic system in action.
“It was our best look yet at a caldera collapse event,” Patrick said. “That was probably our biggest scientific result: We learned that caldera collapses happen in an incremental process.”
Over the course of the eruption, the floor of Halema‘uma‘u crater at Kilauea summit dropped bit by bit during 62 subsidence events, each one accompanied by sizable earthquakes. By the end of the eruption on Sept. 4, 2018, the caldera floor had dropped by more than 500 meters.
“One of the things that did was, it actually compressed the lava in the magma chamber,” Patrick said, explaining that the subsidence at the summit squeezed magma into the lower East Rift Zone like toothpaste through a tube — leading to more fissures opening throughout lower Puna, displacing some 3,000 residents and causing nearly $800 million in economic and infrastructure damage.
Many details about the inner workings of the volcano are still unknown. The second-most recent eruption of Kilauea, which lasted from September 2021 until December 2022, ended within days of the end of an eruption of Mauna Loa, with HVO Scientist-in-Charge Ken Hon hypothesizing at the time that the two volcanoes’ magma systems might be intertwined in some capacity, but adding that more data is needed.
The 2018 eruption, the most destructive volcanic event in the U.S. since 1980 — which Patrick noted also was one of the most productive eruptions of the last two centuries, emitting between 1 cubic kilometers and 1.5 cubic kilometers of material — has left the volcano in a state of “recharge” as its magma chamber refills.
But Patrick added that “as we found out in 2018, things can change quickly.”
Email Michael Brestovansky at mbrestovansky@hawaiitribune-herald.com.
