A typically quiet geyser in Yellowstone National Park erupted last month, spewing water up to 30 feet in the air. Afterward, park employees found a slew of garbage surrounding its vent, including a Hamm's beer can, a vintage pacifier, a shoe heel and dozens of coins.

Curators considered placing the items in the park's archives as a reminder: Please, don't use the springs as a trash can. The park posted a photograph of the "strange" items after last month's eruption of the geyser called Ear Spring.

"Foreign objects can damage hot springs and geysers," said the park. "The next time Ear Spring erupts we hope it's nothing but natural rocks and water."

The pacifier dates back to the 1930s, according to Live Science, which noted a cinderblock, a busted bottle, old signs, cigarette butts and an eight-inch drinking straw among the items.

"Some are clearly historic," the park said in its post. So was the Sept. 15 eruption.

Old Ear had not experienced a known eruption of that size of since 1957, the United States Geological Survey said, though smaller bursts took place as recently as 2004.

After the eruption, a shift in hydrothermal activity occurred in the area around Old Ear known as Geyser Hill, the USGS noted, which is located across the Firehole River from Old Faithful.

"An approximately 8-foot diameter area of surrounding ground is 'breathing' — rising and falling by about 6 inches every 10 minutes," the USGS said in the Sept. 19 update.

"Several other thermal features are more active than usual, including geysering and boiling of Doublet Pool and North Goggles Geyser."

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