January 2023 summit eruption

A large lava lake producing several fountains of lava at night.
Views of the lava lake during the first night of the eruption on January 5, 2023. Lava is visible from most overlooks along Crater Rim Drive.

NPS Photo/M.Newman


Anticipation grew after nearly a month-long pause at the summit of Kīlauea volcano. On January 5, 2023, Hawaiian Volcano Observatory (HVO) geologists recorded heightened earthquake activity and changes in ground deformation. This indicated that magma was on the rise. HVO raised the alert to “watch” and “orange," and at 3:28 p.m. a 3.2 magnitude earthquake joggled visitors at the national park.

Shortly after 4:30 p.m. a surge of lava burst from the floor of Halema'uma'u crater. Visitors and rangers saw awe-inspiring fountains that roared 164 feet (50 meters) into the air. Lava flows inundated the crater floor within hours and filled a 277-acre (112 hectares) area; roughly the size of 240 American football fields.

The only remnants that remained were the higher-elevation "islands" formed during the initial phase of the December 2020 eruption and a ring of older lava around the hardened lava lake from December 2022.

Volcanic activity within Halemaʻumaʻu began to diminish on February 19, 2023. Lava from wihtin Halemaʻumaʻu crater would occassionaly come to the surface through a process called crustal foundering. Foundering occurs when a segment of cool lava crust on the surface of the lava lake is overriddeen by less-dense liquid from below, causing the crust to sink into the underlying lava lake.

On March 7th the eruption paused after 61 days of volcanic activity according to the USGS Hawaiian Volcano Observatory. Geologist observed that lava was no longer flowing on the crater floor.

Map dated February 3, 2023 showing the size of the active and non active portions of the lava lake. Diagram on bottom showing how lava filled Halema'uma'u crater from 2018 to 2023.
Courtesy of the USGS
This reference map depicts the Kīlauea summit eruption as of February 3, 2023. One eruptive vent is active inside Halema‘uma‘u crater, within the actively circulating lava lake (red) on the eastern side of the crater floor. The extent of the active lava lake—the area in red—is 26 acres (11 hectares); part of this area is comprised of the active lava lake footprint from the end of the 2021–22 eruption, which has filled with new lava that upwelled from below. The full extent of new lava from this eruption, totaling both the active lava lake (red) and flows that have crusted over (pink) is 294 acres (119 hectares).

Also included here are west to east topographic profiles across the caldera. Profiles are provided for the periods before the 2018 caldera collapse (orange), shortly after the 2018 collapse (gray), the December 2020–May 2021 eruption (brown), the September 2021–December 2022 eruption (red), and the current eruption (pink) as last modelled from the HVO overflight on January 17. Also shown is the maximum depth of the 2019–20 Halema‘uma‘u water lake (blue).
Visit our keyboard shortcuts docs for details
1 minute, 3 seconds

Increased pressure beneath Halema'uma'u crater led to a 164-foot fountain during the initial phase of the 2023 eruption. In this video, lava outgases at the surface of an active lava lake producing lava fountains.


Last updated: September 18, 2023

Park footer

Contact Info

Mailing Address:

P.O. Box 52
Hawaii National Park, HI 96718


808 985-6011

Contact Us