Summer 2018 Kilauea Eruption

Our sympathy goes out to those who were impacted by this eruption. We are grateful to everyone who worked so hard during the summer of 2018: Civil Defense, Red Cross, National Guard, FEMA, Hawaii Volcanoes National Park, and especially the USGS. For more details on the eruption, visit the web site of the Hawaiian Volcano Observatory. Below is a brief overview.

Past Eruptions

Periodically, lava erupts along Kilauea’s East Rift Zone, and heads downhill towards select areas of Puna. In the past few decades, molten lava has moved relatively slowly through Kapoho, Royal Gardens, and Kalapana. This was the pattern everyone was used to.

A man photographs molten lava along a road
Bruce Omori takes a photo of molten lava crossing a road in Kalapana, in 2010.
Lava flows through a chain link fence
Virginia Aragon captured this image of the 2014 lava flow as it stopped just outside the Pahoa Transfer Station.

Volcanic Activity in Early 2018

In the spring of 2018, Kilauea was inflating, indicating that magma was accumulating beneath the volcano. At the summit, Halemaumau lava lake was active, but downrift at Puu Oo, no lava was visible, despite inflation directly below the vent.

A lake of lava overflows onto the adjacent crater floow
Prior to 2018, the lava lake at the summit of Kilauea was active for many years, sometimes overflowing, as in this 7 May 2015 photo.

The Magma Conduit Widens in May 2018

Many people guessed that there might be a breakout of lava from Puu Oo. But instead, a large earthquake (M 6.9) occurred on 4 May 2018, and the underground conduit between Puu Oo and areas downrift suddenly widened by about 8 feet. This wider conduit allowed magma that had been accumulating under Puu Oo to flow downhill, towards Leilani Estates. The underground magma soon encountered older pods of cooler, stored magma that had been left over from older eruptions (likely including 1955 and 1960.) The new magma pushed out the old magma, which was viscous and therefore moved slowly. Scientists from the Hawaiian Volcano Observatory worked 24/7 to track the eruption; colleagues from the other volcano observatories flew in to lend a hand; Civil Defense ordered residents to evacuate as needed.

Two men walk down a road with cracks
At the start of the eruption, under the guidance of HVO, Bruce Houghton (UH Manoa) joins Tim Orr (USGS Alaska Volcano Observatory), in monitoring cracks that are developing in Leilani Estates.
A man measures gas from a volcanic vent
Alan Lerner, collaborating with the USGS HVO, collects data on volcanic gas emissions in Leilani Estates, at the onset of the eruption.
A woman shows a group of scientists how a drone works
Angie Diefenbach (USGS Cascades Volcano Observatory) joined the HVO team, bringing UAS equipment to track and capture video of the 2018 eruption in Puna; here, Angie shows CSAV International scientists how the UAS operates.
Pumice covers a road.
Pumice ejected from Fissure 8 landed on nearby homes and driveways and roads; note how easily this fragile tephra is crushed under tires from a vehicle.

Lava Begins to Flow Faster

After the initial pods of older, viscous stored magma had been ejected, the fresh magma was able to erupt. This lava was very fluid and moved quickly, and there was an enormous volume of material, since it included magma stored beneath both Puu Oo and Halemaumau. The eruption centered on Fissure 8, which produced spectacular fountaining, with tephra landing on nearby homes and infrastructure. Lava eventually made its way through Leilani Estates and Kapoho, all the way to the ocean, taking out hundreds of homes that were located downhill.

A scientist observes a lava flow
Once the fresher magma was able to erupt, the lava flows became much faster, and for safety, scientists had to keep their distance when making observations and collecting data.
A man photographs a lava flow
The lava from Fissure 8 eventually made its way down to the ocean; here, a scientist attending the UH Hilo CSAV International Course observes the flow at dusk.

The Summit Caldera Collapses

Meanwhile, at the summit of Kilauea, magma was draining from beneath Halemaumau and flowing towards Leilani Estates and Kapoho, through the newly widened conduit deep inside the rift zone. After the magma left the summit, the ground above was no longer supported, and the section of the caldera above Halemaumau Crater began to collapse, at the rate of a meter per day. In areas adjacent to the caldera, cracks appeared along roads and trails, and the National Park wisely closed access to everyone except emergency personnel and scientists. UH Hilo Geology staff and students assisted in documenting the cracks for the Park.

A view of Kilauea Caldera, before and after the collapse
The volume of caldera collapse is about a cubic kilometer, which is equal to the volume of magma that erupted in three months in the area of Leilani Estates and Kapoho.
A scientist observes cracks on a path
UH Hilo Geology Professor Steve Lundblad measures cracks along the asphalt path between KMC and Jaggar Museum; fill beneath the path fell into the underlying graben, causing the asphalt to drop.
A student in field gear observes road damage
UH Hilo Geology student Heather Sexton documents cracks parallel to Crater Rim Drive; note the ash created by the collapse, which blankets the area downwind.

UH Hilo Lends a Hand

One problem with the collapse of Kilauea summit was that the Hawaiian Volcano Observatory building, located on the edge of the caldera, developed dangerous cracks, and staff had to evacuate. Fortunately, at the University of Hawaii at Hilo, spring semester had just ended; both the Geology building, and a large laboratory in the building that houses CSAV, were empty for the entire summer, and available for HVO to occupy as their temporary quarters. This arrangement allowed HVO staff to continue operations without interruption, and also led to enhanced collaboration between the Observatory and UH Hilo, via the CSAV Cooperative Research Agreement with the USGS-HVO.

Scientists work at desks with computers
The Hawaiian Volcano Observatory staff analyzes new data for the 2018 eruption; the team is working out of UH Hilo Geology Building 110, normally a classroom.
Equipment rests on tables and the floor
In Room 123 at UH Hilo, essential monitoring equipment that was evacuated from the HVO Building is stacked on lab tables and floor space, ready for deployment.
A man sits at a long table, preparing gear
In the CSAV Lab, Kevan Kamibayashi, in charge of HVO electronics and telemetry, plans out the design and deployment of field gear for the 2018 Puna eruption.
White sample bags of rocks are lined up on a lab table
UH Hilo Geology Lab 121 became the repository of samples from the 2018 eruption, where UH Hilo Geology majors working under the CSAV Coop Grant quickly prepared the rocks for analysis in the EDXRF, to assist HVO.
A student looks through a microscope
Years before the 2018 eruption, UH Hilo Geology major Valerie Wasser uses a binocular scope to find particles of volcanic glass in samples from Halemaumau, as part of the CSAV Coop grant; comparing chemistry of the 2018 samples and earlier lava was essential to understanding how the magma was evolving.

The Eruption Ends, 4 August 2018

Lava flows in Puna stopped in early August (except for minor activity), and the summit collapse came to a finish as well.

Next, the important work of rebuilding infrastructure could begin, but not immediately—for example, thick lava flows in Puna were still too hot to bulldoze over, for creating new roads. In Hawaii Volcanoes National Park, damage had to be carefully assessed, of buildings, roads, and trails, before work could proceed, for safety.

Surveyors walk across rugged terrain
In July of 2019, government workers check the temperatures of the aa flow that covered the road between Pohoiki and Mackenzie State Park; the young coconut plants mark the foot path used by surfers to access Pohoiki.
A repair truck is parked next to a hole in the road
Road damage in Hawaii Volcanoes National Park was extensive, due to the caldera collapse. Road fill that supported asphalt often was shaken loose during the earthquakes, falling into pre-existing grabens; here, a construction crew prepares for a road repair near Kilauea Military Camp.
Boulders cover a section of a trail
Sections of several trails in Hawaii Volcanoes National Park were heavily damaged during the caldera collapse, as boulders from steep cliff faces fell to the trails below. Fortunately, no one was injured, for the Park kept areas closed until safe.