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Comparison of caldera-forming eruption sizes (by volume of erupted magma) in the U.S., modified from an AVO/USGS figure. Also included for reference is the 1980 eruption of Mount St. Helens. The three caldera-forming eruptions in Alaska are more than 200 times the size of the 1980 eruption of Mount St.
Comparison of caldera-forming eruption sizes (by volume of erupted magma) in the U.S., modified from an AVO/USGS figure. Also included for reference is the 1980 eruption of Mount St. Helens. The three caldera-forming eruptions in Alaska are more than 200 times the size of the 1980 eruption of Mount St.
The location of GPS station KRAC and its predecessor KRAK, slightly north of the center of deflation in Long Valley. USGS figure by Josh Crozier and Alicia Hotovec-Ellis.
The location of GPS station KRAC and its predecessor KRAK, slightly north of the center of deflation in Long Valley. USGS figure by Josh Crozier and Alicia Hotovec-Ellis.
Locations of earthquakes of at least magnitude 1.0 in 2025 and the outlines of the boxes CalVO uses to count earthquakes around Long Valley. Only 6 earthquakes were located inside the Long Valley Caldera box. (Earthquake location data from Northern California Seismic Network.) Figure by Alicia Hotovec-Ellis, USGS.
Locations of earthquakes of at least magnitude 1.0 in 2025 and the outlines of the boxes CalVO uses to count earthquakes around Long Valley. Only 6 earthquakes were located inside the Long Valley Caldera box. (Earthquake location data from Northern California Seismic Network.) Figure by Alicia Hotovec-Ellis, USGS.
Graphs of the number of earthquakes located each year since 1980 in the Long Valley Caldera and nearby Sierra Block monitoring boxes. Note that the number of earthquakes on the left shown on a logarithmic scale, which means they increase an order of magnitude with each "step." Figure by Alicia Hotovec-Ellis, USGS.
Graphs of the number of earthquakes located each year since 1980 in the Long Valley Caldera and nearby Sierra Block monitoring boxes. Note that the number of earthquakes on the left shown on a logarithmic scale, which means they increase an order of magnitude with each "step." Figure by Alicia Hotovec-Ellis, USGS.
Rhyolite lava flow textures from Long Valley and Yellowstone calderas. A) Photograph of well-developed spherulites in a lava flow from Long Valley Caldera in Eastern California. This high-silica rhyolite flow is very similar to the Central Plateau Member rhyolites of the Yellowstone Plateau Volcanic Field and exhibits many of the same textures.
Rhyolite lava flow textures from Long Valley and Yellowstone calderas. A) Photograph of well-developed spherulites in a lava flow from Long Valley Caldera in Eastern California. This high-silica rhyolite flow is very similar to the Central Plateau Member rhyolites of the Yellowstone Plateau Volcanic Field and exhibits many of the same textures.
This panorama of the Long Valley Caldera, looking from north to south, shows its broad central plain, post-caldera rhyolite flows and uplift on the right, and eastern Sierra Nevada in the background. USGS photo by Jessica Ball.
This panorama of the Long Valley Caldera, looking from north to south, shows its broad central plain, post-caldera rhyolite flows and uplift on the right, and eastern Sierra Nevada in the background. USGS photo by Jessica Ball.