A day after the end of episode 12 of the ongoing eruption at Kīlauea's summit, volcanic gas emissions continue from the recently active north and south cones on the western edge of Halema‘uma‘u. Most of the gas consists of water vapor (the primary volcanic gas), with sulfur dioxide (SO2) and other gases. Sulfur dioxide emissions are causing vog downwind of the summit area. When this photo was taken the morning of March 6, the emission rate was approximately 1,200 tons of SO2 per day, similar to other periods between eruptive episodes in the ongoing eruption. USGS photo by N. Deligne.

Lava flows from the eruption which started on December 23, 2024, within Halema‘uma‘u at the summit of Kīlauea volcano, have buried most of the cone from the June 2023 eruption, seen here in the upper middle of photo. This telephoto was taken north of the degassing north and south cones, and is looking toward to the south through the volcanic gas plume. As of March 6, 2025, the ongoing eruption is currently paused. USGS photo by N. Deligne.

USGS Hawaiian Volcano Observatory (HVO) collects tephra from lava fountaining in buckets. Each bucket has a weight inside to prevent high winds from blowing the bucket away; some of these weights are milk jugs filled with sand. On March 6, HVO staff discovered a lava bomb from the episode 12 lava fountains pierced and partially melted a milk-jug-weight in a bucket located several hundred yards west of the western rim of Halema‘uma‘u. USGS photo by N. Deligne.

A view across of the new lava flows on the floor of Halemaʻumaʻu, looking towards the active north and south vents on the west wall of the crater. USGS photo by D. Downs on March 5, 2025.

 

During the lava fountains of episode 12, which reached approximately 300 feet (90 meters) high, tephra particles traveled through the air to be deposited on the crater rim down wind. This clast was about 16 inches (40 centimeters) long. The tephra clasts formed during the recent lava fountains are very bubble rich and delicate, breaking easily when they are moved. USGS photo by D. Downs. 

These thermal maps of the summit caldera at Kīlauea show the activity at two stages of episode 12. On the morning of March 4, the vent activity was just beginning, with a very small flow near the vent in the west portion of the caldera. Small ooze-outs of residual lava were also active. By the next day, March 5, more vigorous activity was present, along with extensive channelized flows on the crater floor and more widespread ooze-outs.

This view of episode 12 of the Kīlauea summit eruption in Halemaʻumaʻu was taken the evening of March 4, 2025, from the Kaluapele overlook near Kīlauea Military Camp in Hawaiʻi Volcanoes National Park. USGS photo by K. Mulliken.

A telephoto image of episode 12's lava fountains show the varied textures of motel material as it leaves the vent. In the fountain you can see the formation of both cinder and spatter. Cinders are glassy, vesicular, pyroclastic fragments that fall to the ground in an essentially solid condition. These are the smaller, darker particles in the figure. Spatter is similar to cinder, except that it is partially molten when it falls to the ground. The left of the image shows a lava flow that is emanating out of the vent complex. The wavy configuration of the plates is caused by lava from the north and south vents flowing alongside one another, similar to how arms of a glacier meet when flowing down a mountain. USGS photo by L. Gallant.

A USGS Hawaiian Volcano Observatory scientist monitors episode 12 of the ongoing Kīlauea eruption during the evening of March 4, 2025. While working in the hazardous closed area of Hawaiʻi Volcanoes National Park, USGS staff wear personal protective equipment, including high-visibility clothing, hard helmets, gas masks, gloves, and eye protection. USGS photo by M. Patrick.