| 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 miles (55 km) by 45 miles (72 km). Last eruption 70000 years ago (magmatic) / 1350 BC ± 200 years (explosive hydrothermal) ongoing (nonexplosive hydrothermal). Yellowstone, lies over a hotspot where light, hot, molten mantle rock rises towards the surface. While the Yellowstone hotspot is now under the Yellowstone Plateau, it previously helped create the eastern Snake River Plain (to the west of Yellowstone) through a series of huge volcanic eruptions. Although the hotspot's apparent motion is to the east-northeast, the North American Plate is really moving west-southwest over the stationary hotspot in the Earth's mantle. Over the past 17 million years or so, this hotspot has generated a succession of violent eruptions and less violent floods of basaltic lava. Together these eruptions have helped create the eastern part of the Snake River Plain from a once-mountainous region. At least a dozen of these eruptions were so massive that they are classified as supereruptions. Volcanic eruptions sometimes empty their stores of magma so swiftly that they cause the overlying land to collapse into the emptied magma chamber, forming a geographic depression called ... |
