Maunaloa’s first eruption in almost four decades is over. And nearby Kīlauea has also gone quiet, scientists said Tuesday. Alert levels for both volcanoes were reduced from watch to advisory.
It’s not uncommon for these two Hawaiʻi Island volcanoes to have simultaneous eruptions. But is it a coincidence that their volcanic activity ended within days of each other?
Hawaiian Volcanoes Observatory geologist Matt Patrick said that while Maunaloa and Kīlauea have distinct magma systems, it is possible they affected one another.
"We also know from research that because they're neighbors, they can feel the stress of one another. So you can imagine a scenario over the past couple of years when Maunaloa has been building up pressure to its recent eruption, that added stress may have stressed the Kīlauea magma chamber and allowed it to sustain that lava lake eruption," he told The Conversation.
"But once the Maunaloa eruption ensued, that caused a very rapid deflation in the Maunaloa summit magma chamber and that may have taken some of that stress off of Kīlauea's chamber and allowed it to relax, maybe depressurize it a little bit," Patrick said. "And kind of maybe been the final point that resulted in this long-term, one-year-long lava lake kind of stagnating."
Patrick said it’s too soon to say when either volcano may erupt again. The U.S. Geological Survey will continue to monitor both closely.
"They each one will erupt again. They're very active volcanoes. But now starts the process of compiling the data and trying to understand better about how the Maunaloa eruption ensued," Patrick said. "We're always trying to improve our knowledge of how lava flows behave and the dynamics of lava flows, and this eruption provided a lot of new data for that."
The Hawaiʻi County Civil Defense Agency said that the viewing route on Old Saddle Road will reduce its hours to 4 p.m. to midnight on Wednesday and then shut down permanently at midnight on Thursday.
This interview aired on The Conversation on Dec. 13, 2022. The Conversation airs weekdays at 11 a.m. on HPR-1.