A video showing the moment a US lake's water disappears down a two-metre hole has emerged on line.
The lake area is left looking more like a park after the water disappears. But there is a geological explanation for the seemingly strange occurrence.
Locals in Oregon say the phenomenon has been occurring for years at Lost Lake, and scientists believe it's caused by a lava tube, which is a tunnel in the earth created to drain away lave during a volcanic eruption.
The video has been uploaded to YouTube with the caption: "Water from Lost Lake drains down one of the many lava tubes scattered throughout the Central Oregon Cascades.
"The water is most likely seeping into the subsurface below and refilling the massive aquifer that feeds springs on both sides of the Cascades."
After the lava flow stops, the underground conduits can harden leaving behind a long, cave-like system with an opening to the surface.
Jude McHugh, a spokeswoman for the Willamette National Forest, told ABC News: "In Lost Lake, this particular lava tube collapsed and became the drain hole for that lake."
She said the lake is constantly draining but it's most evident in the drier months when the rate of draining exceeds the input from precipitation, making the lake look more like a meadow.
Users have written a number of comments underneath the YouTube video, including: "That hole is just selfish and rude", and: "I wonder how many bodies are hidden in there."
According to news.com.au, residents in the area have previously tried to block the hole, but have been warned that could cause a risk of flooding for local homes and businesses.
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