The Tatio ignimbrite was emplaced less than one million years ago, while the Tucle volcanics are dated to 800,000 ± 100,000 years ago. The ignimbrite reaches a volume of and crops out over a surface area of . The Tatio ignimbrite contains rhyolitic pumice and crystals, while the Tucle volcanics are andesitic and include both lava and tuffs. The El Tatio ignimbrite ponded in the Tatio graben and may have originated at the Tocorpuri rhyolite dome, which is less than one million years old, in a vent now buried beneath the El Tatio volcanic group, or at the Laguna Colorada caldera.