Yellowstone is underlain by two magma bodies. The shallower one is composed of rhyolite (a high-silica rock type) and stretches from 5 km to about 17 km (3 to 10 mi) beneath the surface and is …

Dec 22, 2025 · The size of the magma chamber beneath Yellowstone is one of the most fascinating and often misunderstood aspects of the park’s geology. For decades, popular imagination pictured a …

Jan 16, 2026 · Yellowstone Caldera, enormous crater in the western-central portion of Yellowstone National Park, northwestern Wyoming, that was formed by a cataclysmic volcanic eruption some …

The Yellowstone Volcano Observatory monitors volcanic activity and does not consider an eruption imminent. Imaging of the magma reservoir indicates a substantial volume of partial melt beneath …

Blasts from the Past The first major eruption of the Yellowstone volcano, which occurred 2.1 million years ago, is among the largest volcanic eruptions known, covering over 5,790 square miles with …

Jun 18, 2025 · Yellowstone’s magma chamber is mostly made of a light-colored rock called rhyolite. It spreads out over an area roughly 55 miles long and 30 miles wide and reaches down to a depth of …

Apr 16, 2025 · A high-silica type of igneous rock called rhyolite makes up Yellowstone’s magma chamber, which spans an area 55 miles by 30 miles, dropping to a depth of 10 miles below the …

Dec 2, 2022 · Two large reservoirs full of magma exist beneath the Yellowstone Caldera—one that’s about three to ten miles beneath the surface, and another that’s 12 to 30 miles below ground.

Jul 10, 2020 · April 23, 2015 – University of Utah seismologists discovered and made images of a reservoir of hot, partly molten rock 12 to 28 miles beneath the Yellowstone supervolcano, and it is …

Mar 27, 2024 · It is considered one of the largest volcanoes in the world, capable of producing more than 240 cubic miles (1,000 cubic kilometers) of ash, magma, gas, and rock. It has the power to …