Hawaiian man dies after falling into a lava tube hidden in his backyard
In concrete jungles, there's the fear of falling through a sidewalk grate. In parts of Hawaii, there are lava tubes.
They form during volcanic eruptions, starting their lives as rivers of lava and flowing downstream as they branch out into smaller channels like the roots of a tree. Then the exposed lava cools and hardens. A roof forms over the river, allowing the lava beneath it to go on flowing for months until it slows and drains and hollows - becoming a tube.
Despite their ubiquity on Hawaii's Big Island, it's rare for someone to actually fall into a lava tube, experts have said. But it can happen.
And on Monday, police said it happened to an elderly man - in his own backyard.
The man, reportedly in his early 70s, appeared to be trimming branches in his yard this week when he fell "through a soft area of ground" into a hidden lava tube on his property and died, according to a Wednesday statement from police on Hawaii's Big Island.
Police arrived at the man's home in Hilo, on the island's east coast, to perform a welfare check Monday after one of the man's friends called to report him missing, Big Island Now reported. Rescue personnel discovered him resting at the bottom of the two-foot-wide lava tube, 22 feet below ground.
He was transported to the hospital, where he was pronounced dead, police said. An autopsy performed Tuesday found that he died "as a result of injuries consistent with falling," and no foul play is suspected, police said.
It's unclear exactly how the man fell into the lava tube. Ken Hon, a volcanologist at the University of Hawaii at Hilo, told The Washington Post he suspects that the hole was already there and that the man likely just didn't see it ― possibly because it was covered in overgrowth. Plenty on the island are, Hon said. The tubes are everywhere: in neighborhoods and underneath streets, in forests and national parks like an underground cave system right beneath your feet.
"You could be standing on one and not even know it," Hon said.
The holes, he said, are called "skylights." "That's where a thin part of the roof collapses, so you'll have a hole into the lava tube," he said. "If you think of a skylight in a house, it's just a window up in the roof. The skylight is a hole in the roof of the cave."
Hon said he couldn't be certain which volcanic eruption created the lava tube in the man's backyard, or even whether it was definitely a tube. But Hon and two other scientists who spoke with The Post believe there's a good possibility that the lava tube in question formed during the massive 1880-1881 eruption of the Mauna Loa volcano. The lava flowed for months and miles, threatening the town of Hilo as it slowly inched closer. People prayed to God and Pele, the Hawaiian goddess of volcanoes, asking for the lava stop, building ditches and blasting dynamite to try to divert its flow, according to the National Park Service.
More than nine months later, once the rivers of lava eventually stopped, the result was the Kaumana Caves - a 25-mile network of lava tubes.
Tom Shea, a volcanology professor at the University of Hawaii at Manoa, said tube systems are typically structured "in a treelike fashion." The primary tube is the trunk, sometimes stretching 30 or more feet in diameter, while secondary tubes are like branches, growing smaller with distance, he said.