New thermal activity in the Upper Geyser Basin in Yellowstone

Yellowstone National Park reports over the last several days, there has been new thermal activity in the Geyser Hill area of the Upper Geyser Basin.

This includes new erupting vents splashing water on the boardwalks, surface fractures and a rare eruption of Ear Spring on Saturday, September 15.

The eruption ejected not only rocks, but also material that had fallen or been thrown into the geyser in years past, like coins, old cans, and other human debris. The last known similar-sized eruption of the spring was in 1957, although smaller eruptions occurred as recently as 2004.
Geyser Hill lies across the Firehole River from Old Faithful and features dozens of hot springs, geysers and fumaroles.

For the public’s safety some boardwalks and trails in the Geyser Hill area have been temporarily closed. Closure signs are posted.

The boardwalks around Old Faithful remain open.

The outcome of the current changes on Geyser Hill in the Upper Geyser Basin is uncertain. Yellowstone officials say the two most likely possibilities are:

The area of thermally heated ground may expand and continue to cause changes in hydrothermal activity that persist for years, much like the thermal activity of 2003 in the Norris Geyser Basin. This could necessitate rerouting of the current boardwalk configuration. A small hydrothermal explosion could occur in the area, forming a crater a few feet across and ejecting rocks and hot water up to a distance of hundreds of feet, much like that which occurred at Porkchop Geyser in the Norris Geyser Basin in 1989.

Yellowstone officials say changes in Yellowstone’s hydrothermal features are common occurrences and do not reflect changes in activity of the Yellowstone volcano.

There are no signs of impending volcanic activity in the park.