Visitors to Yellowstone's geyser basins are told to remain on the boardwalks that wind through the basins for their own protection/Kurt Repanshek file photo of the Norris Geyser Basin

Editor's note: This updates with the identity of the young man.

A 23-year-old Portland, Oregon, man enjoying the Norris Geyser Basin in Yellowstone National Park with his sister was killed when he wandered nearly 700 feet off a boardwalk in the geyser basin and fell into a hot spring.

Park officials on Wednesday identified the victim as Colin Nathaniel Scott. He was with his sister, Sable Scott, when he fell into an unnamed hot spring near Porkchop Geyser on Tuesday afternoon. His sister called rangers for help after he fell in.

The park release did not say whether his sister had remained on the boardwalk or was roaming the basin with him, or how rangers might attempt to recover the man's remains from the hot spring.

While the Norris Geyser Basin was closed to the public Tuesday evening, it had reopened Wednesday, according to the spokeswoman.

The young man fell into a hot spring in the Back Basin area of the Norris Geyser Basin/Map via National Park Maps, www.npmaps.com

Down through the decades there have been relatively few deaths in the park's hot springs, just 22, according to park records. But with hot spring waters that simmer around 200 degrees Fahrenheit, and thin surface crusts rimming the features that can collapse under an individual's weight without warning, the geyser basins are inherently dangerous. 

"...hot springs deaths have ocurred much more commonly in Yellowstone National Park than have grizzly bear deaths," Yellowstone historian Lee Whittlesey writes in his book, Death In Yellowstone, Accidents and Foolhardiness in the First National Park. "The park has around 10,000 hot springs, geysers, mudpots, and steam vents scattered over its mountain plateau. Though collectively called thermal features today, all are technically hot springs. Most are hotter than 150 degrees F and many reach temperatures of 185-205 degrees F."

The Norris Geyser Basin is both the park's most colorful and hottest. Most of the surface waters in the thermal features are at least 199 degrees (the boiling point at this elevation), the park's website notes.

The last known fatality related to one of the park's hot springs was in 2000, when three concessions workers fell into a thermal feature in the park's Lower Geyser Basin. Sara Hulphers, 22, of Washington state, received the most severe burns and died in a Salt Lake City hospital, park officials said.

Last Saturday a father and son received burns after leaving a boardwalk in the Upper Geyser Basin and wandered into a thermal area.