Coral Geyser is a small clear pool sitting low in a cavern-like opening. Soft and fractured sinter covers the surface area, as does some moss vegetation. Coral Geyser has minimal history of eruptions, mostly after the 1959 earthquake, but since 2004 has had steady splashing activity.

Coral Geyser has an average temperate of 187.5°F (86.4°C), an average pH of 8.4, and an average conductivity of 2000 uS/cm.

Geysers

Geysers have constrictions in their plumbing systems that prevent water from moving freely to the surface where heat would escape. Water beneath the constrictions creates a buildup of steam. Eventually the steam pushes water past the constrictions and the geyser erupts.

Use Caution in Hydrothermal Areas

• Stay on boardwalks and designated trails.
• Hydrothermal water can severely burn you.
• Never run, push, or shove.
• Supervise children at all times.
• Do not scratch hydrothermal mats.

You are responsible for your safety.

Think safety, act safely. Yellowstone is a dangerous place.