Yellowstone’s Black Diamond Pool Erupts, Hurling Mud Up to 40 Feet Into Air
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Yellowstone’s Black Diamond Pool Erupts, Hurling Mud Up to 40 Feet Into Air

21 December, 2025.USA.16 sources

Key Takeaways

  • USGS video shows mud spraying from Black Diamond Pool at 9:23 a.m. in Biscuit Basin
  • Eruption hurled mud and debris up to 40 feet into the air
  • Event is latest of sporadic dirty eruptions at Black Diamond Pool over past 19 months

Yellowstone hydrothermal blast

U.S. Geological Survey scientists captured a clear daytime video showing a muddy eruption at Black Diamond Pool in Yellowstone's Biscuit Basin just before 9:23 a.m. Saturday.

The USGS playfully described the blast as "Kablooey!" as mud sprayed up and out of the pool.

Image from Associated Press
Associated PressAssociated Press

Multiple outlets reported the same footage and timing, noting the event was visible under blue skies and snow and was widely shared by USGS volcano scientists.

The eruption follows a pattern of intermittent shallow hydrothermal blasts at the site that have continued to attract close monitoring.

Hydrothermal explosion context

The December event was framed against a still-lingering hazard from a much larger hydrothermal explosion in July 2024.

Several outlets recall that the July 2024 blast hurled rocks and mud hundreds of feet, damaged a boardwalk, and led park managers to close or restrict access to parts of Biscuit Basin amid safety concerns.

Image from Boston Herald
Boston HeraldBoston Herald

While most sources connect the current "dirty" eruptions to ongoing unstable hydrothermal conditions following that larger blast, some reports cite a July 2024 event at a different nearby pool when describing past damage — a discrepancy in which specific feature was emphasized.

Biscuit Basin monitoring upgrades

Scientists and park researchers beefed up monitoring at Biscuit Basin this summer by adding webcams, seismic and acoustic sensors, and temperature instruments to improve detection and characterization of hydrothermal blasts.

A muddy eruption at Black Diamond Pool in Yellowstone National Park has been captured on camera Muddy eruption at Yellowstone’s Black Diamond Pool captured on videoBy SUSAN MONTOYA BRYANAssociated PressThe Associated Press “Kablooey

breitbartbreitbart

USGS and affiliated observatories say the new instruments helped capture a clear daytime blast, but experts still see no consistent pattern or clear precursors to the 'dirty' eruptions, making them difficult to forecast.

Hydrothermal eruption updates

Officials and scientists characterize the ongoing events as "dirty" hydrothermal eruptions — shallow blasts that can loft mud, rock and steam up to about 40 feet (12 m) — and say they have been occurring sporadically over the past 19 months.

Many recent blasts were audible or obscured by darkness or ice on cameras, making the clear daytime capture of this event noteworthy.

Image from LiveNOW from FOX
LiveNOW from FOXLiveNOW from FOX

Coverage across outlets mixes practical safety notes about closures and damage with descriptive detail about the spectacle and hazards of the blasts.

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