Mount St. Helens
Located in Washington state Mount St. Helens is considered a dacite volcano. A dacite volcano is light in color and made up of volcanic rock with heavy concentration of silica and potassium. The volcano is the most active in the Cascade range and was formed 275,000 years ago through four separate stages. The main portion also known as the edifice, of older St. Helens was formed sum 12,800 years prior. The newest edifice which is part of the lower crater was formed about 3,000 years ago. St. Helens had a steam eruption in 1980. Following the eruption came periods of quiescent followed by a small eruption. Mount St. Helens will most likely erupt again but it is hard to find out when and at what magnitude.
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