Earlier this month, a camera detected a plume of smoke coming from Biscuit Basin in Yellowstone National Park. In the days that followed, authorities investigated the area and discovered that a small explosion had created several new vents and pools milled with steaming water.
In 2024, the same area, specifically the Black Diamond Pool—experienced a larger hydrothermal vent. Again, the latest incident “underscores the dynamic and dangerous nature of hydrothermal activity in the region,” the Yellowstone Volcano Observatory noted. blog post For the US Geological Survey (USGS). After the 2024 event, Biscuit Basin was closed to the public. However, various monitoring stations set up around the area may have caught hydrothermal vents at an unprecedentedly close distance, which experts hope will advance our understanding of these spectacular but dangerous phenomena.
In pursuit of the unexpected
According to the Yellowstone Volcano Observatory, hydrothermal vents are “violent and dramatic events that result in the rapid ejection of hot water, steam, mud, and rock fragments.” These eruptions occur as a result of sudden pressure changes from the rapid transition of liquid water to steam.
Hydrothermal vents are by no means unique to Yellowstone, but they are relatively common in the park, Yellowstone geophysicist Michael Poland wrote in his article. USGS explainer Poland noted that although scientists all over the world have known about hydrothermal explosions for a long time, they still have not been able to definitively identify their precursors.
“Unfortunately, the changes are widespread in hydrothermal areas and are usually recognized only as precursors to background eruptions,” Poland added. “In natural thermal areas around the world, despite the loss of life in some cases, the dangers posed by hydrothermal vents are underestimated.”
Successful hit
Given the unpredictability of hydrothermal vents, officials installed New temporary monitoring stations around Black Diamond Pool after the 2024 event. According to a recent USGS paper authored by a team of experts collaborating with Poland and the Yellowstone Volcano Observatory, this was the perfect call as the camera was pointed toward the eruption on the morning of June 13.
The following day, geologists began investigating the area, as the explosion and associated acoustic signals were coming from the general direction of Black Diamond Pool. However, the team noted in a blog post that the temperature sensors “showed only a very small bump” that bore no resemblance to the pool’s thermal profiles from previous explosions.
Boiling changes
As the investigation progressed, the team found that the last explosion had caused numerous, albeit small, changes to the area. First, three sets of newly formed vents—passageways for hydrothermal vents—pushed hot water into the Firehole River north of Black Diamond Pool. The water temperature at the time was about 194 degrees Fahrenheit (90 degrees Celsius), so the boiling point was slightly lower, experts said.
When the team returned a few days later, they were in for an even bigger surprise. A section of the ground “where the team had gone just two days before” turned into a “boiling, gray, silty” pool about 21 × 17 feet (6.5 × 5.3 meters) in size. Cross-referenced with Discovery camera data showed that the pool resumed geyser-like behavior on June 18.
Scientists are currently sorting through data sets collected by monitoring stations in the Biscuit Basin. In a blog post, they said there was a “good chance” the explosions were recorded from a distance of about 238 feet (100 meters), which would make this the closest observation of similar events. The team hopes that this new data will give them clues that will help them identify possible precursors to hydrothermal vents.
