(BIVN) – Episode 15 in the ongoing Kīlauea summit eruption began at 12:04 p.m. HST on Tuesday, March 25th. 

Much like Episode 14, the latest eruptive episode is starting with continuing cycles of lava rise, fountaining and vigorous overflows, and drainback events. 

High lava fountaining has yet to occur during this latest episode, as of Tuesday afternoon.

USGS webcam shows Kīlauea summit just before sunset on Tuesday

From a Tuesday afternoon update by the USGS Hawaiian Volcano Observatory:

Episode 15 was preceded by eight cyclic, small spatter fountains in the north vent that began at approximately 9:27, 9:55, 10:11, 10:29, 10:48, 11:07, 11:27, and 11:45 a.m. HST on March 25 and lasted for 5-10 minutes each. The ninth cycle lasted from 12:04-12:19 p.m. HST and produced vigorous overflows that extended 150 to 300 feet (50-100 meters) into Halemauʻamaʻu crater. Activity increased in activity with subsequent events from at 12:25-12:39, 12:47-13:02,13:08-13:23, 3:29-13:39, and 13:46- 13:58 p.m. HST. These continued to increase in intensity with fountains up to 30-50 feet high (10-15 meters) from the north vent. Around noon, the south vent also became active and is feeding a lava flow out onto the crater floor. Flows from both vents have covered about 5% of the floor of Halemaʻumaʻu crater at this time. High fountaining has not yet begun, but is expected to follow the cyclic fountains and drainbacks as it did during episode 14.

Inflationary tilt reached just over 5 microradians since the end of the last episode recovering more than 100% of the tilt lost from episode 14. Seismic tremor began increasing with cyclic fountains and drainbacks, and tilt at SDH switched from inflation to deflation at about 1 p.m. HST, about the same time lava flows began erupting onto the crater floor.

Emissions of SO2 gas during episodes 13 and 14 have exceeded 40,000 tonnes per day and similar amounts of gas are expected to accompany fountain eruptions during episode 15. Currently winds at the summit are predicted to be weak, which may allow the plume of gas to spread around the summit region of Kīlauea. In addition, visitors to Hawaiʻi Volcanoes National Park and residents of adjacent towns may be exposed to Peleʻs hair and other small fragments of volcanic glass being carried in the plume.

Each episode of Halemaʻumaʻu lava fountaining since December 23, 2024, has continued for 13 hours to 8 days, and episodes have been separated by pauses in eruptive activity lasting less than 24 hours to 12 days.