Mount St. Helens Volcano Landscape

Mount St. Helens is an active volcano in North America. It is located in the northern Cascade Mountains in Washington State in the northwestern United States and has an elevation of 2,950 m. This volcano had been dormant for 123 years when it suddenly erupted on March 27, 1980. The eruption on May 18 was the most violent; the volcanic clouds reached an altitude of 20,000 m, and volcanic ash was dispersed over an area of 4,000 km². The ash was 1.8 cm thick over an area of 800 km²around the volcano. Rivers near the volcano were clogged and diverted, and many roads were buried. The lava flows caused forest fires that killed all living creatures within tens of kilometres of the volcano. Melting of large amounts of ice and snow caused turbulent rapids and flows and combined with the condensation of water vapour in the rising air to cause hazardous torrential rains, which carried the volcanic ash as mud flows that ran down from the peak and destroyed agricultural fields, forests and...