Marci Allen

 Yellowstone National Park has a variety of elements that were discussed in class  Not only is it a hot spot, as mentioned, but it is the home to volcanoes, earthquakes, hot pots, and wild fires. Note: All photographs were taken by Marci Allen unless indicated otherwise

 The Yellowstone Caldera is the largest volcanic system in North America  Also known as “super volcano”  The Caldera’s first eruption occurred 640,000 years ago  Since then, there have been more than 80 eruptions  A caldera is created when a magma chamber collapses, causing a massive eruption.  There are no predictions of when the next eruption will occur.

 Yellowstone has 300 geysers (2/3 of the total geysers in the world)  The most famous geyser is Old Faithful  The largest geyser is the Steamboat Geyser  Yellowstone contains 10,000 other geothermal features

 More than 137,000 eruptions have been recorded  Shoots 3,700-8,400 gallons of water up to 185 feet  Eruptions last minutes  Earthquakes have caused time between eruptions to increase  In 1939 the average interval was 66.5 minutes but now the average is 90 minutes Old Faithful

 Yellowstone experiences thousands of small earthquakes each year  There have been six earthquakes with a magnitude of 6 or higher  In 1959 there was 7.5 earthquake that caused a landslide that broke a dam on Hebgen Lake, creating a new lake called Quake Lake  28 people died  Caused geysers to erupt Hebgen Lake

 Lightening causes 35 fires each year  People cause 6-10 fires each year  Most fires burn about an acre of land before they burn out  To reduce threats, controlled burns are performed  In 1988 there was an extreme drought  Seven fires burned 793,000 acres of land in just a few months  More regulations and restrictions were created to prevent this from happening again Fire near Yellowstone in 2007