My family and I decided to visit Mount St. Helens in Washington. My children noticed that it appeared to be a mountain rather than a volcano as it had snow around the top. I explained to my children is not only is it a volcano, but it is an active volcano. It is so tall I explained because of the layers of ash and pumice it has acquired over time with each eruption. Its last great eruption had occurred in 1980. This explosion had caused damage where not only where things destroyed such as lumbar camps, but people had died. I told them not all volcanoes erupt the same way, however Mt. Saint Helens was an explosive eruption in 1980 due to an earthquake that causes a landslide which exposed the gas filled molten to lower pressure causing an explosive reaction. In addition, if the lava has more crystallization it will cause the lava to be thicker preventing gasses from releasing which also makes it more explosive. I then told my children volcanoes that are explosive are known as composite volcanoes compared to shield volcanoes in which lava flows down. My children looked at the surrounding trees and asked how this volcano emerged in this area. I explained it is not uncommon for volcanoes to come into existence in subduction zones where one plate is sliding under another. Specifically, Mt. St. Helens was created when the Juan de Fuca plate subducted under the North American Plate. My children looked at this huge volcano with amazement and came to the realization how even volcanoes can have great height and if active can still be very dangerous no matter how many years are between eruptions.
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