Harrowing video shows the moment a volcanic explosion caused molten rock to barrel through the roof of a sightseeing boat off Hawaii, injuring 23 people.
Coast Guard officials have stopped tour operators getting up close to where Kilauea volcano’s lava oozes into the sea following Monday’s incident that saw 12 people taken to hospital.
A woman in her 20s was transported to Honolulu in serious condition with a broken thigh bone, while the other injured people were treated for minor burns and scrapes.
The Coast Guard, state and local officials were investigating what happened.
Officials have warned of the danger of getting close to lava entering the ocean, saying the interaction can create clouds of acid and fine glass.
Despite the hazards, several companies operate such tours.
Vessels are usually prohibited from getting closer than 984 feet (300 meters) from where the lava meets the sea.
The agency had been allowing experienced boat operators to apply for a special license to get closer up to 164 feet (50 meters), but it stopped allowing those exceptions Monday morning.
Shane Turpin, the owner and captain of the vessel that was hit, said he never saw the explosion.
He and his tour group had been in the area for about 20 minutes making passes of the ocean entry about 1500 feet (460m) offshore, Mr Turpin said.
He did not observe “any major explosions,” so he navigated his vessel closer, to about 750 yards (228 meters) away from the lava.
“As we were exiting the zone, all of a sudden everything around us exploded,” he said. “It was everywhere.”
The molten rock is coming from the Kilauea volcano, which has been erupting continuously for the past 35 years.
The US Geological Survey says explosions of varying sizes occur whenever 1,093C (2,000F) lava enters much colder seawater.
Kīlauea #LERZ status update: lava in the channel is a bit lower with no significant overflows. At the coast, the southern margin of the flow is about 0.5 miles from the boat ramp at Isaac Hale Park. https://t.co/JBahcQaP6N pic.twitter.com/cqWkudIHhZ— USGS Volcanoes🌋 (@USGSVolcanoes) July 18, 2018
Monday’s large blast may have been amplified by the relatively shallow water at the point where the lava entered the sea. That is because explosions occur much closer to the surface in such spots.
The volcano has also been pumping more lava into the water now compared to past years.
Kilauea is sending to the sea as much as 26 times the amount of lava per second than it did during a 2016-17 eruption.
In May, its eruption entered a new phase when it began spurting lava through newly formed fissures in a residential neighbourhood.
It has destroyed more than 700 homes since then. But the only serious injury over the past two months was to a man who was hit by flying lava that broke his leg.
- Press Association