Comparing Mt. St. Helens to Kilauea
Of the volcanoes that are located in the United States there are two which are world renowned for their activity and their power to change the region surrounding them. The two volcanoes would be Mount Saint Helens and Mount Kilauea. In order to get a better understanding of these volcanoes we will be comparing and contrasting them as well as talking about how they were formed and when they last had an eruption. Let’s begin with Mount St. Helens which is located in the pacific northwest of the United States. To be more specific it is located in Washington State and is a part of the Cascade mountain range that spans from California to Canada. It is a composite volcano, which has steep sides that are formed by alternating layers of lava flow, and pyroclastic material made up of ash and other debris. These types of volcanoes have a tendency to have very explosive eruptions and pose a great many problems for people and animals nearby1. This is in contrast to the volcanoes found in Hawaii which have slow flowing lava eruptions and few if any massive explosions. Mount St. Helens is formed by a subduction zone where the Juan de Fuca Plate plunges beneath the North American Plate causing the uplifting of the Cascade Mountains. The last eruption took place on May 18, 1980 and had such a force that was compared to 500 Hiroshima atomic bombs going off at once2. Once the explosion went off, it lead to a blast that generated a 2.8km3 mud flow that moved 22 miles at a speed of 157 miles per hour. Many studies have been done that show there is a large rotating block under it which causes friction that was likely the cause of the eruption2. When Mount St. Helens exploded when a 5.1 magnitude earthquake went off one mile below the volcano causing the bulge that had been building for months after the collapse of the summit, to suddenly collapse on the north flank. The mudflow and lava that would follow would kill many animals and 57 people. They do not know when it will erupt
Bibliography: 1. http://mountsthelens.com/ 2. http://0-go.galegroup.com.catalog.poudrelibraries.org/ps/retrieve.do?inPS=true&prodId=GVRL&userGroupName=fcollinspl&docId=GALE%7CCX1918700958&contentSegment=&searchId=R1&tabID=T003&resultListType=RESULT_LIST&currentPosition=1 3. http://www.buzzle.com/articles/mount-kilauea-volcano-hawaii-volcano.html 4. http://www.georesources.co.uk/kilauea.htm