Friday, May 15, 2015

Yellowstone Supervolcano

Yellowstone River flowing
through the Yellowstone Caldera
Geophysicists have long recognized that the Yellowstone Caldera, lined by a mountainous ridge and overlying a supervolcano that last erupted 640,000 years ago, covers most of Yellowstone National Park.

A seismic imaging study conducted by geophysicists from the University of Utah indicates the volcanic plumbing and magma chamber underlying Yellowstone is more voluminous than realized.
A volcano may be considered as a cannon of immense size.
Oliver Goldsmith, Goldsmith’s Miscellaneous Works, 1841
A University of Utah video animation shows the extent of the volcanic plumbing and magma reservoir revealed by the imaging study (below).

Yellowstone magma reservoirSource: University of Utah

Color Key

Green line Yellowstone National Park boundary
Orange Previously known magma chamber (3 - 9 miles beneath the surface)
Red Previously unknown magma reservoir (12 - 28 miles beneath the surface)
Yellow Hotspot plume that supplies molten rock from Earth's mantle
Black line Boundary of the caldera
White dots Epicenters of earthquake data used in the study

Our earth is very old, an old warrior that has lived through many battles. Nevertheless, the face of it is still changing, and science sees no certain limit of time for its stately evolution. Our solid earth, apparently so stable, inert, and finished, is changing, mobile, and still evolving. Its major quakings are largely the echoes of that divine far-off event, the building of our noble mountains. The lava floods and intriguing volcanoes tell us of the plasticity, mobility, of the deep interior of the globe.
Reginald Aldworth Daly