Mud Volcano Trail

Yellowstone itself is a volcano, and one of its most spectacular eruptions occurred 640,000 years ago. During the eruption, the land collapsed and left a large depression in the earth—the Yellowstone Caldera. This caldera filled with lava flows over hundreds and thousands of years creating the volcanic plateau that comprises much of the central part of the park. Here at Mud Volcano you are close to one of the resurgent domes. The hills you see east of here comprise Sour Creek Dome. Resurgent domes are areas of active ground deformation, where the land moves up or down with the fluctuation of the magma chamber below. Scientists monitor these domes closely for information about ongoing volcanic activity. Not surprisingly, many of the park’s geysers, hot springs, mudpots, and fumaroles are also found near or within the caldera.