(BIVN) – The ongoing eruption at the summit of Kīlauea volcano remains paused, with the next episode of lava fountaining still expected to begin towards the end of this week.  

Scientists with the USGS Hawaiian Volcano Observatory calculate Episode 35 is likely to start between October 17 and 21.  

Seismic tremor indicates that gas piston events continue within the vents, but are more irregular compared to the past several days, geologists noted in recent days. Magma is close to the surface, as evidenced by the incandescence visible in both the north and south vents overnight. 

USGS webcam view of the Kīlauea summit on Wednesday morning

On Sunday night, short spatter bursts were observed from both the south and north vents. 

UPDATE – (10 a.m. ) – From the USGS Hawaiian Volcano Observatory on Wednesday morning:

Summit Observations:

Halemaʻumaʻu continues to be quiet this morning with passive outgassing plumes rising from the north and south vents. Incandescence was visible in the north vent and south vents last night, with south vent incandesces being mostly continuous starting around 10 pm on October 14. Continuous seismic harmonic tremor started sometime during the day on October 14. The UWD tiltmeter shows continued inflationary tilt and as of this morning, the tiltmeter has recovered a total of approximately 20.6 microradians since episode 34 ended. Inflation rates since Sunday, October 12, have been lower than normal at less than 1 microradian a day.

Episode 34 occurred over about 6 hours on October 1 and included lava fountaining from both the north and south vents. Lava fountains reached an estimated 1300 feet (400 meters), and both the north and south vents generated lava flows that covered a large portion of the western part of Halemaʻumaʻu. Episode 34 was preceded by several days of precursory activity, with over 120 gas piston events that produced small, sporadic spatter fountains 10 feet (3 meters) high and numerous short overflows of lava from the north vent. Deflationary tilt at UWD totaled approximately 26 microradians during episode 34 fountaining, with an estimated volume of approximately 12 million cubic yards (9 million cubic meters or 2.5 billion gallons) of lava erupted overnight. The dual fountains also produced a record combined effusion of 500 cubic yards per second, about twice the maximum eruptive rate measured in previous episodes.

USGS webcam view of the Kīlauea summit on Wednesday morning

Rift Zone Observations:

Rates of seismicity and ground deformation remain very low in the East Rift Zone and Southwest Rift Zone, with no significant earthquake activity in the past 24 hours outside of the summit. Sulfur dioxide (SO2) emissions from the East Rift Zone remain below the detection limit.

Analysis:

The steady continuation of inflationary tilt following the end of episode 34 coupled with periods of strong glow indicates that the summit magma reservoir is repressurizing and is likely to lead to another lava fountaining episode. Variable glow from both the vents last night, and continuous termor indicate that magma is at high levels within both vents. The open nature of the south vent suggests it is still likely to play a prominent role in the next episode after staging a dramatic comeback in episode 34. Models of inflation continue to indicate that the start of episode 35 is likely to occur between October 17 and 22, with the most likely dates being between October 18 and 20.

The current eruption has been characterized by episodic lava fountaining not seen in any eruptions since the 1983–86 episodic fountains at the beginning of the Puʻuʻōʻō eruption. Lava fountains and flows have erupted from two vents within Halemaʻumaʻu crater that we refer to as the north vent and south vent. Each of the previous fountaining episodes lasted from a few hours to over a week and was accompanied by strong deflation of the summit region. Pauses between the lava fountaining episodes have been marked by an immediate switch from deflation to inflation as the magma chamber recharges and repressurizes. Lava fountaining episodes have occurred approximately once per week since the start of the current eruption on December 23, 2024.

HVO continues to closely monitor Kīlauea and is in contact with Hawai‘i Volcanoes National Park and the Hawai‘i County Civil Defense Agency about eruptive hazards.