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USGS YVO Monitors Volcanoes in 6 U.S. States

The USGS arm of the Yellowstone Volcano Observatory monitors volcanic activity in Montana, Wyoming, Utah, Colorado, Arizona, and New Mexico.

Map of western U.S. with volcanic ashfall outlines.
Map showing the minimum area covered by volcanic ash from eruptions of Valles Caldera, Mount St. Helens, Yellowstone, and Long Valley Caldera.

The formal structure of Yellowstone Volcano Observatory (YVO) includes a consortium of 9 organizations who's scientists collaborate to study and monitor the active geologic processes and hazards of the Yellowstone Plateau. The U.S. Geological Survey arm of YVO is also responsible for monitoring and reporting activity for volcanoes in the southwestern U.S. These volcanoes are primarily dispersed volcanic fields that behave differently than Yellowstone. Valles Caldera in New Mexico is the exception, which currently hosts a hydrothermal system and resurgent dome. The area has had 2 caldera-forming eruptions in the past 1.6 million years.

YVO Area of Responsibility

Wyoming, Montana, & eastern Idaho




New Mexico