Little Change to Lava Lake Depth at Halemaʻumaʻu Crater

8:35 AM HST Tuesday, Dec. 29, 2020: USGS Hawaiian Volcano Observatory

Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

This photo, taken at approximately 5:30 a.m. December 29, 2020, shows Kīlauea’s ongoing summit eruption. The western vent in the wall of Halema‘uma‘u continued to erupt overnight, and the northern/eastern vent remained inactive. At approximately 3:45 a.m. HST today (Dec. 29), HVO field crews measured the lava lake as 179 m (587 ft) deep. USGS photo by H. Dietterich.

Lava activity continues to be confined to Halemaʻumaʻu with lava erupting from a vent on the northwest side of the crater. As of 4 a.m., the lava lake was 587-591 feet deep with a narrow black ledge around it. The west vent continued erupting lava into a lava lake within Halemaʻumaʻu crater with two or three narrow channels visible this morning.

Reduced, but still elevated, SO2 emissions were measured on Monday.

Preliminary analysis of sulfur dioxide emission rates measured Monday show that the rates about 3,300 tonnes/day — slightly lower than the Dec. 27 rate of 5,500 t/d, but still elevated; both values were in the range of emission rates common for the pre-2018 lava lake.

High levels of volcanic gas, rockfalls, explosions, and volcanic glass particles are the primary hazards of concern regarding this new activity at Kīlauea’s summit. Large amounts of volcanic gas—primarily water vapor (H2O), carbon dioxide (CO2), and sulfur dioxide (SO2)—are continuously released during eruptions of Kīlauea Volcano.

HVO scientists monitor the ongoing Kīlauea summit eruption from within an area of Hawai‘i Volcanoes National Park that remains closed to the public for safety reasons. They are equipped with a range of specialized safety gear and personal protective equipment such as gas masks, helmets, gloves, and eye protection. No major changes were observed at the eruption site overnight and this morning: the west vent remains active and continues to feed the lava lake. USGS photo by L. DeSmither.

The lake volume was slightly more than 29 million cubic yards or 5 billion gallons. The most recent thermal map taken Monday, it lake dimensions as 840 by 535 yards for a total area of 72 acres. The narrow 11-22 yard ledge around the lake was about 1-2 yards above the active lake surface.

Over the past day, the main island of cooler, solidified lava floating in the lava lake drifted slowly westward in the lake until about 10 p.m. Monday when it stalled along with 10 or so much smaller islands to the east. The main island measured about 820 feet in length, 440 feet in width, and about 7 acres in area based on the Dec. 28 thermal map. This morning, the main island is still stalled but is rotating slowly. Measurements on Dec. 27 show that the island surface was about 20 feet above the lake surface.