99-12AP Mount St. Helens Before 1980 Art PrintThis scene shows Mount St. Helens and Spirit Lake as it appeared around 1950–1979. At that time, the area in the Gifford Pinchot National Forest was serene and enjoyed by many people for fishing, canoeing, and swimming. In 1952, the mountain was measured at 9,671 feet in elevation.After studying the ring growth of some fallen trees near Spirit Lake in 1939, a botanist concluded that a major eruption around 1802 of volcanic ash and pumice from Mount St. Helens had suppressed the growth of nearby trees for several years. The botanist's discoveries were not the only evidence of recent volcanic activity. The first recorded eruption of Mount St. Helens happened in 1835, as reported by the physician at Fort Vancouver. Missionaries also witnessed an 1842 eruption. In 1978, the U.S. Geological Survey published a paper in the journal, Science, warning that Mount St. Helens would erupt again, perhaps before the end of the century. Their reports were largely ignored - until 1980. After over 100 quiet years, the mountain reawakened in the spring of 1980. Magma pushed up in the volcano, causing earthquakes and small ash emissions for 6 weeks. The May 18, 1980 eruption caused the largest landslide in recorded history, sliding into Spirit Lake and down the North Fork Toutle River valley (to the right in this painting). A vertical column of ash erupted from the newly-formed crater to a height of 12 miles. The ash, spread eastward by prevailing winds, circled the earth in 2 weeks. When the ash cleared, Mount St. Helens was 1,300 feet shorter, Spirit Lake was much larger, and the lush green forest, for 150 square miles north of the crater, had been transformed into a blown-down, grey landscape. It was obvious that the powerful natural forces that were responsible for the Pacific Northwest's famed beauty were not just ancient history, but an ongoing natural process. |
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