The Yellowstone Plateau volcanic field developed through three volcanic cycles spanning over two million years and including two of the world's largest known eruptions.


The >2450 km3 (588 mi3) Huckleberry Ridge Tuff erupted about 2.1 million years ago, creating a large, approximately 75 km (47 mi) wide, caldera and thick volcanic deposits. A second cycle concluded with the eruption of the much smaller Mesa Falls Tuff around 1.3 million years ago. Activity subsequently shifted to the present Yellowstone Plateau and culminated 640,000 years ago with the eruption of the >10003km (240 mi3) Lava Creek Tuff and consequent formation of the 45 x 85 km (28 x 53 mi) caldera. Large volumes of rhyolitic lava flows (approximately 600 km3 (144 mi3) were erupted in the caldera between 180,000 and 70,000 years ago, distributed primarily along two north-south alignments of vents. No magmatic eruptions have occurred since then, but large hydrothermal explosions have taken place during the Holocene, including near Yellowstone Lake. Uplift and subsidence of the ground surface is centered on two uplifted regions (the Mallard Lake and Sour Creek resurgent domes). Large earthquakes occur just off the plateau along the nearby Teton and Hebgen Lake faults, the latter of which ruptured in 1959 (Ms = 7.5), causing considerable damage to the region. Yellowstone is presently the site of one of the world's largest hydrothermal systems including Earth's largest concentration of geysers.


Date published: October 19, 2020

Yellowstone's tool-making lava flows

Yellowstone has a lot to offer visitors, from its world-famous hydrothermal features to its vast array of wildlife and breath-taking scenery. Yellowstone has also provided humans with another important resource for the last 11,000 years or more—obsidian.

Date published: October 12, 2020

A time when Old Faithful wasn’t so faithful

Old Faithful Geyser got its unique name in the 19th century because its eruptions were so regular and predictable. But during parts of the 13th and 14th centuries, the geyser did not erupt at all.

Date published: October 5, 2020

Modernizing geodetic infrastructure at YNP: The best data for the best science

Fall is a time for maintaining monitoring sites in Yellowstone, since they will not be accessible during the winter months.  That includes the continuous GPS stations that track deformation across Yellowstone National Park!

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