(BIVN) – Kīlauea volcano is not erupting, but recent activity has prompted an information statement from scientists on Wednesday afternoon. 

The USGS Hawaiian Volcano Observatory reported that the elevated rates of seismicity that were observed beneath Kīlauea’s summit and upper East Rift Zone between June 27 and July 1 have decreased. However, summit region unrest continues. 

“Seismic unrest may continue to wax and wane with changes to the input of magma into the area,” the USGS HVO said. “This unrest is consistent with increasing pressurization of the magmatic system underlying the Kīlauea summit region.”

The volcano alert level and aviation color code for Kīlauea remain at ADVISORY/YELLOW. 

“Current conditions are not indicative of an imminent eruption, but this could change rapidly,” scientists stated. “Prior eruptions in the summit region have occurred with very little warning.” 

At this time, there have been no closures within Hawaiʻi Volcanoes National Park due to the current unrest.

USGS: “While HVO geologists were moving temporary webcams, they revisited the site of the June 3 eruption. This photo looks downrift, with the June 3 pad of lava in the upper right. Extensive cracking uprift of the fissure had weak residual outgassing and vibrant sulfur deposits.” (USGS photo by M. Patrick)

From the USGS HVO information statement:

RECENT OBSERVATIONS

Kīlauea last erupted on June 3, 2024. That eruption occurred approximately 3 km (2 miles) southwest of Kaluapele (Kīlauea caldera) within Hawai’i Volcanoes National Park. That eruption lasted less than 9 hours and generated small lava flows that covered about one third of a square mile (one half of a square kilometer). Since that eruption, patterns of seismicity and ground deformation indicate that magma has been re-accumulating in the storage regions beneath the summit.

Between June 27 and July 1, 2024, approximately 1,500 earthquakes were detected beneath the south part of Kaluapele and Kīlauea’s upper East Rift Zone (UERZ). Earthquake locations were concentrated between Keanakākoʻi and Pauahi craters, beneath Chain of Craters Road in Hawaiʻi Volcanoes National Park. Activity peaked during the late evening of Saturday, June 29, when more than 30 earthquakes were occurring per hour. Most events were smaller than magnitude-2, but there were several earthquakes large enough to be felt in Hawaiʻi Volcanoes National Park and in neighboring communities, including five earthquakes magnitude-3 or higher. The earthquakes occurred at depths of 1–4 km (0.6–2.5 mi) below the ground surface. This seismic unrest was not accompanied by any significant changes in ground deformation.

As of July 2, rates of seismicity have decreased to levels observed prior to June 27, but summit region unrest continues. Unrest may continue to wax and wane with changes to the input of magma into the area.

USGS: “This map shows recent deformation at Kīlauea, over the timeframe of June 13 to June 29, 2024. Data was recorded by the Italian Space Agency’s (ASI) Cosmo-SkyMED satellite. Colored fringes denote areas of ground deformation, with more fringes indicating more deformation. Each color cycle represents 1.5 cm (0.6 in) of ground motion. The bullseye feature indicates inflation of the area southwest of Kaluapele over this time period. The northeast-southwest trending line-like feature reflects the intrusion (body of magma underground) that fed the June 3, 2024, eruption. Arrow in the upper left indicates satellite orbit direction (arrow) and look direction (bar).”

INTERPRETATION AND CONTEXT 

Pit craters and lava flows in the UERZ are evidence of a long history of magma moving along this rift zone pathway. Intrusions of new magma into this region have been monitored numerous times in the past decades, with sparse eruptions. During the past 60 years, there have been approximately 50 intrusions and 5 eruptions in the UERZ region. The last UERZ eruption took place in November 1979. That was a brief one-day eruption that occurred in and near Pauahi Crater and was preceded by two months of increased earthquake activity along with inflation at the summit region. Several other UERZ eruptions took place in the early 1970s and lasted from one day to about a month. UERZ eruptions have typically occurred near the southeast margin of Kaluapele, or where the UERZ meets the middle East Rift Zone near Pauahi Crater.

Recent seismic unrest in the UERZ reflects higher levels of summit pressurization and does not necessarily indicate that future unrest will continue, or that an eruption may occur, in this region. For example, similar seismic swarms occurred beneath the UERZ in April and May 2024, but seismic unrest subsequently moved away from the UERZ and became focused at other locations south of Kaluapele and toward the Southwest Rift Zone prior to the June 3 eruption.

USGS: “Aerial image of the Southwest Rift Zone eruption of Kīlauea, viewed during an overflight at approximately 6 a.m. on June 3, 2024.” (USGS image)

WHAT WE CAN EXPECT

It is not possible to forecast an exact outcome of this activity. Future eruptions are possible with little warning within Kaluapele (Kīlauea caldera), south of Kaluapele, or along the upper portions of Kīlauea’s rift zones. Since 2020, five eruptions have occurred within Kaluapele, and one eruption has occurred southwest of Kaluapele, with as little as 1 hour or less of advanced warning in the form of accelerated rates of ground deformation and earthquakes.

Here are some possible scenarios that could play out in the coming days to weeks:

Magma continues to accumulate beneath Kīlauea’s summit, resulting in intermittent periods of unrest but no immediate intrusion or eruption (similar to periods of unrest that occurred in April and May 2024). In this scenario, episodes of earthquakes and ground deformation would continue at varying rates at varying locations including beneath Kaluapele, south of Kaluapele, and the upper rift zones.

Magma continues to accumulate beneath Kīlauea’s summit, resulting in an eventual intrusion (similar to what occurred during the January/February 2024 intrusion southwest of Kaluapele). In this scenario, we would expect to see accelerated rates of ground deformation and earthquakes in the direction of the intrusion as it occurs, along with summit deflation.

Magma continues to accumulate beneath Kīlauea’s summit, resulting in an eventual eruption inside Kaluapele (similar to what occurred during the 2020-2023 eruptions). In this scenario, we would expect to see signs of the magma reservoir beneath Halema‘uma‘u rapidly pressurizing prior to accelerated rates of ground deformation and earthquakes beneath Kaluapele before lava reaches the surface.

Magma continues to accumulate beneath Kīlauea’s summit, resulting in an eventual eruption outside of Kaluapele but within the general summit region or upper extents of the rift zones (similar to what occurred during the June 3, 2024, eruption). In this scenario, we would expect to see earthquake locations migrating away from Kaluapele, followed by accelerating rates of ground deformation and earthquakes before lava reaches the surface.

WHAT WE ARE DOING

HVO continues to closely monitor Kīlauea, watching for any signs of unrest that may precede a new eruption. HVO is in frequent communication with Hawai‘i Volcanoes National Park and Hawai‘i County Civil Defense to keep them apprised of the activity.

With permission from Hawai‘i Volcanoes National Park, HVO staff deployed a temporary webcam near Cone Peak to monitor the upper Southwest Rift Zone of Kīlauea: [S1cam] – View of the upper Southwest Rift Zone of Kīlauea, view is to the south

With permission from Hawai‘i Volcanoes National Park, the KOcam was deployed to Maunaulu to monitor the upper East Rift Zone in May and is available here: [KOcam] Live Image of upper East Rift Zone from Maunaulu

HVO will continue to issue daily updates for Kīlauea, and additional notices as necessary.