What is a geyser cone?

A geyser cone is created when hot, mineral-rich water repeatedly erupts from a geyser and deposits minerals around the vent. Over time, these deposits build a cone-shaped structure, often made largely of silica. Not all geysers form cones; some instead erupt from open pools or fractures. The famous Old Faithful geyser in Yellowstone is often associated with a cone feature around its vent. These structures record the long-term activity of geothermal systems and can continue growing as eruptions add more mineral layers.