The Yellowstone Plateau in northwestern Wyoming has a long geologic history-earthquakes expanding and retreating glaciers rising mountains powerful geothermal explosions and cataclysmic volcanic eruptions, the most recent of which was the Yellowstone Supervolcano, which erupted 640,000 years ago. Via ArcGIS, website users expand their perspective of Yellowstone through layers of information.Web mapping includes a mashup of live data feeds, high-resolution digital elevation models, and an array of geologic datasets.The central clearinghouse of information was built with ArcGIS for Server.
Yellowstone is presently the site of one of the world's largest hydrothermal systems including Earth's largest concentration of geysers. 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. Uplift and subsidence of the ground surface is centered on two uplifted regions (the Mallard Lake and Sour Creek resurgent domes). No magmatic eruptions have occurred since then, but large hydrothermal explosions have taken place during the Holocene, including from within and near Yellowstone Lake. Large volumes of rhyolitic lava flows (approximately 600 km 3 (144 mi 3) were erupted in the caldera between 180,000 and 70,000 years ago, distributed primarily along two north-south alignments of vents.
Activity subsequently shifted to the present Yellowstone Plateau and culminated 640,000 years ago with the eruption of the >1000 3km (240 mi 3) Lava Creek Tuff and consequent formation of the 45 x 85 km (28 x 53 mi) caldera. A second eruption cycle concluded with the much smaller Mesa Falls Tuff around 1.3 million years ago. The >2450 km 3 (588 mi 3) Huckleberry Ridge Tuff erupted about 2.1 million years ago, creating an approximately 75 km (47 mi) wide caldera and thick volcanic deposits.
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