Scientists in Hawaii have captured rare images of blue flames burning from cracks in roads as Kilauea volcano gushes fountains of lava in the background, in a new dimension in the weeks-long eruption.
The volcano produces methane when hot lava buries and burns plants and trees. The gas flows through the ground and up through existing cracks.
“It’s very dramatic. It’s very eerie,” said Jim Kauahikaua, a US Geological Survey scientist. He said it was only the second time he had seen blue flames during an eruption.
The methane can seep through cracks several feet away from the lava. It can also cause explosions when it is ignited while trapped underground. These blasts can toss blocks several feet away, said Wendy Stovall, also a scientist at the USGS.
Hawaii County has ordered about 2,000 people to evacuate Leilani Estates and surrounding neighbourhoods since the eruption began on May 3.
The volcano has opened more than 20 vents in the ground that have released lava, sulphur dioxide and steam. The lava has been pouring down the flank of the volcano and into the ocean miles away.
The eruption has destroyed 50 buildings, including about two dozen homes. One person was seriously injured after being hit by a flying piece of lava.
Ms Stovall said lava spatter from one of the vents was forming a wall that was helping protect a nearby geothermal plant.
Lava from that vent was shooting further into the air and producing the highest lava wall of all the vents, which was blocking molten rock from flowing north towards the plant.
Officials shut down Puna Geothermal shortly after the eruption began.
On Tuesday, officials finished stabilising wells that bring up hot liquid and steam to feed a turbine generator.
A team from the Hawaii Emergency Management Agency and the company continued to plug the wells to make sure the fluid inside does not move from one part of the well to the other, said Janet Snyder, a spokeswoman for Hawaii County.
Sorry about the bad link.. For daily status updates on #Kilauea visit our Hawaiian Volcano Observatory website - https://t.co/veaTXUpPbz— USGS (@USGS) May 22, 2018
Also be sure to follow @USGSVolcanoes pic.twitter.com/S01qeUzXxL
Earlier this month officials removed a flammable gas called pentane from the plant to reduce the chance of explosions.
Tourism officials cheered news that a Norwegian Cruise Lines ship that tours the Hawaiian islands would resume stopping in Kailua-Kona next week.
Businesses catering to tourists on the cruise have taken a hit since the company suspended Big Island port visits after the eruption began.
The company said it would resume calling on Hilo, a town on the eastern side of the island closer to the lava, when conditions allow.