The Pacific Northwest is one of the most beautiful areas that you will find in the United States. It is filled with some of the most breathtaking mountains that one could only imagine. We may look at them and think that they are just mountains that have grown over geological time, but they are more than that. In reality, a lot of them are volcanoes. The most popular one is Mount St. Helens. Mt. St. Helens is located in southwest Washington, just 50 miles northeast of Portland, Oregon. It is one of the peaks of the Cascade Range of the Pacific Northwest. I, along with thousands of other people, have taken the opportunity to climb Mt. St. Helens. With its stunning and incredible views from the peak, you also get a surreal feeling that is a little discomforting. Maybe it could be because Mt. St. Helens is very much still alive.
Mt. St. Helens started to grow during the Pleistocene Epoch. It started with dacite and andesite eruptions that existed of hot pumice and ash. Large mudflows flowed down the volcano, which have become important pieces to the eruptive cycles of this volcano. Later, there was another eruptive period, along with the pyroclastic flows of hot pumice and ash, was dome growth. Mt. St. Helens has been one of the most active volcanoes, but has experienced long periods when it has been dormant as well. It was considered a composite volcano, which was a symmetrical cone with steep sides. Most composite volcanoes are known to have explosive eruptions, which could be very dangerous to life and property nearby. From 40,000 years go until its most dramatic eruption in May 1980, Mt. St. Helens continues to show us life still exists within it. Within the last 2000 years, Mt. St. Helens has “been more active than any other volcano in the United States” (Orr 96).
There were extensive glaciers that covered Mt. St. Helens that were created during the Ice Ages of the last few hundred thousand years. Unfortunately, a lot of the evidence that was recorded regarding those glaciers were sparse or removed by erosion and/or buried in the volcanic debris. Mt. St. Helens has created a new glacier. With the help of rock debris and avalanche snow that shed from the steep crater walls; a new glacier has emerged. By 1996, it was obvious in photographs and observations of the new glacier. The steep crater walls provide shade to the glacier and protect it from sunlight most of the year. By 2004, the glacier had grown into a horseshoe shaped feature that had wrapped itself around the lava dome. Due to the small eruption in October 2004 and the continuous growth of the lava dome, the glacier has eventually turned into two arms. The glacier was officially given a name, Crater Glacier, by the U.S. Board of Geographic Names on June 6, 2006 (USGS).
Volcanism occurs in the Cascade mountain range when there is subduction of the Juan de Fuca plate off the west coast moving eastward towards North America. Typically, this means the...