MEDIA RELEASE

The hot crack near the sea cliff, in the immediate area of the ocean entry, has widened significantly over the past four days. On Saturday, January 28, the crack was 30 cm wide (1 foot). Today, HVO geologists in protective gear briefly entered the area and measured the crack as being 75 cm (2.5 feet). In this image comparison, the yellow stars show corresponding points in the two images. The arrow also shows how much the crack has widened.
Remarkably, grinding noises could be heard coming from the crack, and the block of sea cliff on the makai (ocean) side of the crack could be seen to move slightly. These signs indicate that the section of sea cliff around the ocean entry is highly unstable and could collapse at any time. Photo taken Wednesday, February 1, 2017 courtesy of USGS/HVO

KÄ«lauea Volcano’s episode 61g lava flow is still active and entering the ocean at Kamokuna on the volcano’s south coast. Recent observations of the ocean entry indicate growing instability of the adjacent sea cliff. Potential collapse of the cliff poses an extreme danger to anyone in the closed area on land, as well as to boats near the ocean entry.

On January 25, HVO geologists noted an extensive crack running parallel to the sea cliff about 5 – 10 m (16 – 33 ft) behind the stream of lava at the Kamokuna ocean entry. Ground inspection of this crack by HVO geologists on January 28 showed 30 cm (about 1 foot) of separation across the crack. Four days later, on February 1, this crack had widened to about 70 cm (2.5 feet). The seaward block bounded by this crack was visibly moving up to 1 cm (about 1/2 inch), possibly in response to explosions below the ocean entry as hot lava mixed with cool ocean water. In addition, ground shaking could be felt up to several hundred meters (yards) away.

These observations show that this portion of the sea cliff is highly unstable and could collapse into the ocean with no warning.

Sudden collapse into the ocean of a slab of sea cliff about 28 m (90 ft) high and about 150 m (490 ft) or more in length would create a significant wave that would travel rapidly out to sea. It would also could shower the immediate area with blocks of hot rock and fragments of molten lava. It could also prompt more powerful explosions as the 61g lava tube is further exposed.

HVO continues to monitor the situation and will issue further updates as new information becomes available. Photographs of this crack and activity at the ocean entry can be found on our web site: https://hvo.wr.usgs.gov/multimedia/

For more information on hazards associated with lava entering the sea, please see: https://pubs.usgs.gov/fs/2000/fs152-00/