2018 Eruption and Summit Collapse

Large smoke plume emanating from a volcanic shield
Puʻu ʻŌʻō on May 4th, 2018, following a magnitude 6.9 earthquake that shook the Island of Hawaiʻi (USGS Photo)

Prelude to Hulihia

Hulihia: "overturned; a complete change, overthrow; turned upside down."
-Hawaiian Dictionary (Pukui & Elbert)

In March 2018, Kīlauea was erupting in two different places, an uncommon phenomenon that had been happening for nearly a decade: at the summit in Halemaʻumaʻu crater, and down the East Rift Zone at Puʻu ʻŌʻō. These two long-lasting eruptions changed drastically in the middle of March, when USGS scientists discovered a signficant increase in pressure in the magma system below Puʻu ʻŌʻō. With the pressure increasing at Puʻu Ōʻō, the summit of Kīlauea also started to show similar signs of inflation. The lava lake in Halemaʻumaʻu soon began to rise. By April, pressure increased so much that the lava lake overflowed onto the crater floor, drawing over 10,000 park visitors per day.

Two Eruptions End, Another Begins

On April 30th, the summit of Puʻu ʻŌʻō collapsed, an event that USGS scientists have since determined marked the end of the 35-year eruption which first began in 1983. 48 hours after the Pu'u ʻŌʻō collapse, the lava lake at the Kīlauea summit started to drop significantly. Magma started to drain away from the summit of the volcano, moving underground to the middle and Lower East Rift Zone, marked by a series of earthquakes.

On May 3rd 2018, the first fissure of the eruption opened up in a residential subdivision, Leilani Estates. The following day, on May 4th, the island was struck by a magnitude 6.9 earthquake as magma continued its move to the Lower East Rift Zone. Over the next two months, lava covered 13.7 square miles of land, several dozens of feet deep in places. The flows in the Lower East Rift Zone destroyed 700 homes, displaced over 2,000 people, covered 30 miles of road, and added an astounding 875 acres of new land to the island.
Aerial view of steaming volcanic crater
Subsidence of Halemaʻumaʻu crater, June 12th, 2018 (USGS Photo)

Summit Collapse

As the summit adjusted to the withdrawal of magma further down in the rift zone, it caused powerful earthquakes and collapse events up top. Every 28 hours on average, the ground within the summit caldera of Kīlauea sank. These collapses were followed by large air-borne plumes of ash. This dramatic cycle continued through July 2018, dramatically re-shaping the summit landscape of Kīlauea. From May through August, over 60,000 earthquakes shook the area.

As a result of the activity from the 2018 eruption, Halemaʻumaʻu crater grew from 280 feet (85m) deep to about 1,600 feet (488m) deep, and the diameter more than doubled. By September the eruption had concluded. Though the drama of the 2018 eruption ended, Kīlauea remains one of the most active volcanoes in the world.

Chart illustrating the large collapse of Kīlauea caldera in 2018 in relation to the Empire State Building
Chart from the USGS Hawaiian Volcano Observatory illustrating the 2018 caldera collapse
Kīlauea Summit - Before & After Collapse
Kīlauea summit on November 28, 2008 Kīlauea summit on August 1, 2018
Kīlauea summit on November 28, 2008 Photo courtesy USGS - Hawaiian Volcano Observatory
Kīlauea summit on August 1, 2018 Photo courtesy USGS - Hawaiian Volcano Observatory
USGS - Hawaiian Volcano Observatory: Before and after. At left is a photo taken on November 28, 2008, with a distinct gas plume rising from the vent that had opened within Halema‘uma‘u about eight months earlier. At right is a photo taken on August 1, 2018 after the massive summit collapses earlier in the summer. Drag center circle/line left and right to reveal the photos.

Kīlauea Summit - Before & After Collapse
NASA image taken on January 14, 2003 USGS photo taken on August 7, 2018
NASA image taken on January 14, 2003
USGS photo taken on August 7, 2018
Drag center circle/line left and right to reveal the before and after photos from the summit collapse in 2018.


Last updated: March 16, 2021

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