Mount St. Helens (Washington)

          Mount St. Helens is a still active stratovolcano that is located in Washington state.  St. Helens is simply a mountain as well as an active volcano.  As a result, the top of the mountain is indented or taken off most likely as a result of past eruptions blowing of the top part of the mountain.  The guide had explained to me that this mountain is formed as a result of Juan De Fuca tectonic plate being subducted under the North American plate.  As the Fuca plate gets subducted deeper into the earth, it melts and this magma starts rising towards the crust forming the mountain and possibly an eruption.  I learned that  this stratovolcano is only about 40,000 years old so it is fairly young and was formed during the Quaternary Period during the late Cenozoic Era.  This location remains one of the most popular natural laboratories for studying the earth and remains the most active volcano in the Cascade Range.  Visiting this region has some great views and was and is a great experience. 

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