Abyss Pool is one of the deepest hot springs in Yellowstone National Park.

Abyss Pool is one of the deepest hot springs in Yellowstone National Park. (Image credit: Diane Renkin/NPS)

A human foot was found in a hot spring at the park.

An employee of the park found a foot encased in a shoe in the deepest pool in the park. Authorities said that the foot is linked to an incident involving a single individual on the morning of July 31 and that they don't suspect foul play. They didn't say why they don't suspect foul play or who died. The investigation is still going on.

Many of the springs in the area are hot enough to cause burns. Under the weight of someone stepping on them, the mineral crust around the springs can crack. A young man from Oregon died in 2016 when he slipped into a hot pool while trying to take a dip in a closed area. According to USA Today, the pool was very acidic and very warm. The man's body was seen floating in the hot spring by park officials, but they were not able to retrieve it. They didn't find the remains when they came back the next day.

According to the park report, the extreme heat and acidity of the water quickly dissolved his body in the hot spring.

A map of Yellowstone's hot springs by type.

A map of Yellowstone's hot springs by type.  (Image credit: USGS Scientific Investigations Report 2017–5022–P)

An acid-sulfate hot spring is where the man died. The hot springs in the northeastern part of the park are heated by acidic steam so strong that it can eat away rocks and minerals around them. The volcano mud and artists paint pots are acid-sulfate features.

A lot of the pools in the park are basic. Zero is the most acidic, seven are neutral, and 14 is the most basic on the scale. One of the park's alkaline pools has a pH of 8.65 according to a paper published in a book. Baking soda is more basic than the pH of 8.6. The fluids that carry chloride below the surface give the pools their alkalinity.

There is a pool near a lake. According to the National Park Service, it is up to 53 feet deep.

It's not clear if the person died from the heat of the water or the heat of the springs. It's not surprising that the foot inside the shoe was the one that showed the death. Feet detach as the soft tissues of the feet and ankles degrade, as bodies left in water naturally decomposition. Modern shoes will float once set free. There have been 21 human feet that have washed up in the Pacific Northwest.

It was originally published on Live Science