yellowstone national park
A view of a hot spring at the Norris Geyser Basin at Yellowstone National Park on May 12, 2016. Getty

A man who died in horrific circumstances after falling into a dangerously hot and highly acidic thermal spring in Yellowstone National Park has been named as 23-year-old Colin Nathaniel Scott from Portland, Oregon.

Scott was visiting the park in north-west Wyoming on Tuesday (7 June). He was seen by his sister, Sable Scott, walking off the designated boardwalk in the Norris Geyser Basin area, and slipping and falling into a small hot spring about 200m away, close to Porkchop geyser.

The area is notorious for being the hottest, oldest and most dynamic of the park's thermal areas, with springs that can reach temperatures of 200F (93C).

Rescue efforts were hampered by the dangerous thermal conditions and highly fragile ground, with rangers soon treating the incident as a "probable fatality".

On Wednesday, the park confirmed his death and said personal effects belonging to Scott had been retrieved.

"They were able to recover a few personal effects," park spokeswoman Charissa Reid said. "There were no remains left to recover."

Park rangers said he fell into a small pool, adding: "The subsurface waters are super heated and also have very high acidity."

A thin crust, that can appear like solid ground, makes up large parts of Yellowstone. It is formed when minerals dissolved by the high water temperatures are redeposited on the surface. "It's very fragile rock and can be thin as a skiff of ice," said Reid.

Despite numerous signs warning visitors not to stray from the boardwalks, every year rangers rescue people who either fall or wander off designated paths. Many suffer serious burns when they break through the fragile ground beneath them into boiling water.

At least 22 people are known to have died from hot spring-related injuries in Yellowstone since 1890, park officials said.

On Saturday, a 13-year-old boy suffered burns to his ankle and foot after falling into a hot pool in Yellowstone's Upper Geyser Basin. The accident occurred after the child was being carried by his father, who then slipped.

More than four million people visited the park last year, with fatalities or injuries a rare occurrence.

Park Superintendent Dan Wenk said: "We extend our sympathy to the Scott family. This tragic event must remind all of us to follow the regulations and stay on boardwalks when visiting Yellowstone's geyser basins."

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