The latest eruption of Kilauea is following in the footsteps of previous eruptions.
On Sunday afternoon, lava once again spilled to the surface at the summit of Kilauea, breaking a nearly three-month-long period of inactivity after the volcano’s previous eruption, which began June 7, went into a “pause” June 19.
Ken Hon, scientist in charge at the U.S. Geological Survey’s Hawaiian Volcano Observatory, said this latest eruption is indeed a new eruption and not a continuation of the June eruption, as indicated by lava emerging from a different line of fissures in Halema‘uma‘u Crater.
This new fissure line, Hon said, is a long one, measuring about 1.5 kilometers from end to end. The fissures run from the eastern portion of the crater floor and down the eastern wall of the “downdropped block,” the section of the crater that subsided by more than 500 meters during the 2018 eruption.
Hon said the new fissures run more or less parallel with fissures that opened during eruptions in 1982, 1975 and 1954, all of which pointed in the general direction of Kilauea Iki Crater to the east.
“What that actually means, we don’t know,” Hon said.
The eruption began rather suddenly, Hon said. After a period of elevated seismic activity over the past month, he said the volcano has been relatively quiet the last few days, until a tiltmeter detected a strong shift in ground terrain shortly before lava broke out.
Based on initial measurements, Hon said this new eruption is more vigorous than the last, although he added that it is difficult to accurately make such comparisons so early into a volcanic phase that could last months.
“It’s like every other eruption in that there is a very high initial rate of emission that decays rapidly,” Hon said. “When an eruption starts, lava comes out in this strong initial pulse that weakens over time.”
Hon added that early measurements of volcanic gas emissions can also be unreliable, as emission rates can decline rapidly after the start of an eruption — if researchers arrive at the eruption site just a few hours later, the rate can be significantly lower.
But, he said, initial measurements indicated that the volcano was expelling gas at a rate of 190,000 tons per day, adding that the volcano is not likely to sustain such a rate for long. That rate, he said, is higher than the initial emission rate of the June eruption, “but again, they all start high.”
So far, not enough time has passed for researchers to develop a model of how much material has been expelled from the newest fissure.
But for the time being, the eruption seems squarely focused on the volcano’s summit. Hon said there were initial indications of underground lava moving south of Halema‘uma‘u Crater, but those signs have ceased. He also said there is no indication of lava entering the Lower East Rift Zone.
“It is very beautiful,” Hon commented, and advised that sightseers should visit sooner rather than later, before the initial burst of activity fizzles out.
The National Park Service urged visitors at the Hawaii Volcanoes National Park to drive with caution and expect long waits at parking spaces. The Keanakako‘i viewing area in the park is currently closed due to high amounts of volcanic gas and ash.
Email Michael Brestovansky at mbrestovansky@hawaiitribune-herald.com.
