Images

Ground tilt associated with episodic eruptions at Kīlauea. Top panel, two years of summit tilt spanning episodic fountaining at Maunaulu in 1969, as measured by a watertube tiltmeter at Uēkahuna  bluff.  Middle panel, an ideal aerosmith measurement of summit ground tilt during the initial years (1984-1986) of the Puʻuʻōʻō eruption that span a period o

Aerial view of Kaluapele, the summit caldera of Kīlauea, hours after the end of episode 16 of the ongoing eruption in Halemaʻumaʻu. USGS photo by K. Lynn. 

During a monitoring flight on April 2, 2025, USGS Hawaiian Volcano Observatory geologists captured this aerial view of Halemaʻumaʻu, within Kaluapele (Kīlauea summit caldera), just after the end of episode 16 of the ongoing eruption.

USGS Hawaiian Volcano Observatory geologists captured this view during a monitoring overflight just after noon on April 2, 2025, following the end of episode 16 of the ongoing eruption in Halemaʻumaʻu.

During each eruptive episode in Halemaʻumaʻu, tephra is deposited on the crater rim downwind within the closed area of Hawaiʻi Volcanoes National Park. This sign for the Southwest Rift Zone of Kīlauea, which used to stand at least 6 feet (2 meters) above the ground surface, provides a visual for how thick the tephra deposit is at this location. USGS photo by K.

Episode 16 of the ongoing eruption in Halemaʻumaʻu stopped just after noon today, April 2, 2025. On a USGS Hawaiian Volcano Observatory monitoring overflight within the hours following its end, the crater floor was a patchwork of active and inactive lava flows.

USGS Hawaiian Volcano Observatory geologists landed briefly on the floor of Halemaʻumaʻu crater and captured this image of an active ʻaʻā lava flow. Episode 16 of the ongoing eruption at Kīlaeua summit had ended a couple of hours prior to this photo being taken, and several lava flows retained residual activity at the time of the monitoring overflight.

Kīlauea summit eruption episode 16 lava fountain and its lava flow on April 1, 2025. The lava fountain was reaching heights of more than 650 ft (200 m) at times and feeding a lava flow that as of noon on April 1 reached about 2,300 ft (700 m) from its vent. The lava fountain was also depositing a tephra blanket to the northwest that was reaching Highway 11.

Helicopter overflight view of episode 16 lava fountain and its lava flow on the crater floor of Kaluapele at around noon on April 1, 2025. The lava flow at this time had traveled 2,300 ft (700 m) from the fountain along the floor of Halemaʻumaʻu. USGS photo by D. Downs.

Kīlauea summit lava fountain from the west end of Halemaʻumaʻu and the tephra blanket it has produced through its 16 episodes. In some places, the tephra blanket reaches more than 5 ft (1.5 m) thick. Most of the tephra from episode 16 lava fountain on April 1, 2025, was blowing to the northwest, with some clasts reaching Highway 11. USGS photo by D. Downs.

USGS Hawaiian Volcano Observatory geologist captured this aerial view during a monitoring helicopter overflight of episode 16 at around noon on April 1, 2025.  The lava fountain feeds a lava flow from the western end of Halemaʻumaʻu.

On April 1, lava fountains from Kīlauea's ongoing summit eruption prevented geologists from accessing the rim of Halemaʻumaʻu crater within the closed portion of Hawaiʻi Volcanoes National Park. Instead, they hung back along the closed portion of Crater Rim Drive to collect samples of tephra that was intermittently blown in their direction.

On April 1, a USGS Hawaiian Volcano Observatory geologist captured this zoomed-in photo of the upper portion of the active lava fountain during Kīlauea's ongoing summit eruption.

Late in the evening on April 1, USGS Hawaiian Volcano Observatory geologists watched the ongoing Kīlauea summit eruption from Kūpinaʻi Pali (Waldron Ledge). This view of the active eruptive vents was captured through the lens of a laser rangefinder device the geologists were using to measure lava fountain heights. USGS photo by M. Zoeller. 

Episode 16 lava fountains were visible from Highway 11 in Kaʻū on April 1. In this view, the top of the lava fountain is just visible above Halemaʻumaʻu crater rim, and Uēkahuna (the highest part of the caldera rim) is visible to the left. USGS photo by K. Mulliken. 

The episode 16 eruption plume was transported north-northwest on April 1, over Highway 11 in Kaʻū. USGS Hawaiian Volcano Observatory volcanic gas specialists traversed under the plume on the highway in order to get a sulfur dioxide emission rate for episode 16.

Episode 16 lava fountains deposited tephra and Pele's Hair on Highway 11 in Kaʻū on April 1. In this photo, taken around 3:30 p.m. HST, the tephra and Pele's Hair is visible along the centerline and on the shoulder of the highway. USGS photo by K. Mulliken. 

USGS Hawaiian Volcano Observatory geologists captured this aerial view of Kīlauea summit on April 1, 2025, during a helicopter overflight about 3 hours after high fountaining started during episode 16 of the ongoing eruption. USGS photo by N. Deligne.

Wind conditions during episode 16 of the Kīlauea summit eruption resulted in material from the lava fountains being deposited on Highway 11 on April 1. This photo shows the amount of material, including tephra and Pele's Hair, that had accumulated by 3:30 p.m. HST. A Hawaii County Civil Defense Agency message at 12:49 p.m.

Lava fountaining during episode 15 of the summit eruption at Kīlauea volcano. USGS webcam image.

This compilation shows thermal maps made shortly after three different lava fountaining episodes at the summit of Kīlauea. Each fountaining episode produced short-lived lava flows in the western portion of the crater floor, near the vent, which were inactive and solidified by the time of the thermal maps.