Since the episodic lava fountaining eruption at the summit of Kīlauea started in December of 2024, Kīlauea’s summit has cycled through repeating patterns of inflation or ground swelling, brief fountaining, and then deflation or subsidence. That repeating pattern of ground deformation is what has allowed USGS scientists to provide forecasts for when future fountaining episodes could start.
Aloha, it's your weekly Volcano Minute, brought to you by the USGS Hawaiian Volcano Observatory.
Since the episodic lava fountaining eruption at the summit of Kīlauea started in December of 2024, Kīlauea’s summit has cycled through repeating patterns of inflation or ground swelling, brief fountaining, and then deflation or subsidence. That repeating pattern of ground deformation is what has allowed USGS scientists to provide forecasts for when future fountaining episodes could start.
But following the most recent fountaining episode, number 54 on August 25th, the pattern of ground deformation became irregular. The summit reached the inflation level required to start a fountaining episode on September 7th, when small magnitude earthquakes began to occur in the summit region. Low-level eruptive activity happened for the next week, with over 100 lava flows from the north vent, and spatter building a 30-foot-high cone around the vent.
And on the night of September 14th, new vents opened on and near the northwest wall of Halemaʻumaʻu crater. These new vents have fed lava flows on the crater floor, with no fountaining.
Kīlauea summit remains at an elevated level of pressurization and earthquakes continue so what are the possible outcomes? The eruption might continue as lava flows from the new vents, activity could switch back to lava fountains from the main vent complex, or magma could begin to establish new pathways to the surface within the summit region. Alternatively, magma could migrate into the upper portion of the Southwest Rift Zone or the East Rift Zone in Hawaiʻi Volcanoes National Park. In this scenario, we would expect to see more extreme changes in ground deformation patterns and many more earthquakes occurring.
Regardless of what scenario unfolds, scientists at the USGS Hawaiian Volcano Observatory are closely monitoring Kīlauea’s summit, and we’ll issue additional messages in the event of any future changes.
Mahalo for listening, I’m Katie Mulliken and this was your weekly volcano minute brought to you by the USGS Hawaiian Volcano Observatory.