Yellowstone Caldera

The Yellowstone Caldera is the volcanic caldera located in Yellowstone National Park in the United States, sometimes referred to as the Yellowstone Supervolcano. The caldera is located in the northwest corner of Wyoming, in which the vast majority of the park is contained. The major features of the caldera measure about 34 by 45 miles. The last full-scale eruption of the Yellowstone Supervolcano, the Lava Creek eruption which happened nearly 640,000 years ago, ejected approximately 240 cubic miles of rock, dust and volcanic ash into the sky.Geologists are closely monitoring the rise and fall of the Yellowstone Plateau, which measures on average 0.6 inches  yearly, as an indication of changes in magma chamber pressure. The source of the Yellowstone hotspot is controversial. Some geoscientists hypothesize that the Yellowstone hotspot is the effect of an interaction between local conditions in the lithosphere and upper mantle convection. Others prefer a deep mantle origin (mantle plume). Part of the controversy is due to the relatively sudden appearance of the hotspot in the geologic record. Additionally, the Columbia Basalt flows appeared at the same approximate time, causing speculation about their origin.