Yellowstone National Park, another Volcanic System above a Hot Spot (Grades 7-8)
Hawaii Volcanoes National Park is not the only national park sitting above a hot spot. Yellowstone National Park in
northwest Wyoming is famous for its geysers and hot springs. The geysers and hot springs are the result of heat generated
by magma within the crust (and groundwater near the surface). The magma is from a hot spot beneath northwest Wyoming.
Although both parks result from hot spot volcanism, they differ considerably in many ways. Yellowstone developed on
continental crust, not oceanic crust. The last eruption of a caldera at Yellowstone was 600,000 years ago, about the time
that Mauna Loa was just starting to grow on the ocean floor. Eruptions at Yellowstone can produce great volumes (hundreds to
thousands of cubic kilometers) of rhyolitic ash that can cover large areas of the western United States. Eruptions in Hawaii
rarely exceed one cubic kilometer in volume and produce basaltic lavas that typically travel only a few kilometers. Because
of their rhyolitic composition, eruptions at Yellowstone are extremely violent. In contrast, gentle eruptions in Hawaii have
been watched by millions of visitors.
Photographs of Yellowstone are available at the homepages of
University of Montana School of Forestry, and the
University of Utah Seismograph Stations.
Yellowstone is one of the worlds largest volcanic systems.