Lava Lake at Halema‘uma‘u Crater Reaches 718 Feet in Depth

9:46 AM HST Saturday, Feb. 20, 2021: USGS Hawaiian Volcano Observatory

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

It’s been two months since lava returned to the summit of Kīlauea, ending a two-year period of inactivity.

Lava from the west vent continues to supply the lava lake within Halema‘uma‘u crater. According to USGS Hawaiian Volcano Observatory, the active portion of the lava lake is around 17 acres. That is smaller than it was two months ago because the activity is confined to the western side of Halemaʻumaʻu, but it is probably still the biggest lava lake on earth.

Officials described the current lava lake as “passive” where an external vent is filling a crater, similar to the Kīlauea Iki lava lake of 1959.

Despite occasional drops in the lava lake level, the overall trend of the lava level is rising, officials stated. The most recent lava level measurements were about 718 feet deep on Feb. 19. This level is still approximately 148 feet below where the lava is expected to be visible from Kīlauea Overlook within Hawai‘i Volcanoes National Park.

The small increase in depth since Feb. 18 coincides with current effusion rates and slight inflationary trend. The eastern portion of the lava lake, however, has a stagnant and solidified surface crust. SO2 emission rates on February 19 remain elevated at 1,100 t/day.

Seismicity remains stable, with elevated tremor and no minor earthquakes. SO2 and H2S emissions from Puʻu ʻŌʻō were below instrumental detection levels when measured on January 7.

The position and dimensions of the main island have not changed. Yesterday’s field measurements on February 19 show the west end of the island was 16 feet above the lava lake surface; all other islands also remain stationary, frozen in the stagnant eastern portion of the lava lake.