Overview

• Discovered during routine maintenance on April 10, the 13-foot-wide pool in the Porcelain Basin registers about 109 °F at its surface and sits roughly one foot below its rim.
• High-resolution satellite imagery shows no sign of the pool on December 19, 2024, a small cavity by January 6 and a fully formed water pool by February 13.
• Infrasound sensors installed in 2023 detected multiple low-level acoustic signals from late December through early February without accompanying seismic activity.
• Field geologists documented rocks up to 30 cm in diameter coated in light-gray silica mud around the site, indicating a series of minor hydrothermal explosions formed the basin.
• USGS and Yellowstone Volcano Observatory say the pool poses no immediate threat to visitors and will remain under continued geothermal monitoring.