Alaskan volcanoes are famous because of their explosive and frequent eruptions. The Novarupta volcano eruption was the largest eruption of the twentieth century. It took place in a very remote area. A party of explorers and scientists did not visit the area until four years after the eruption. The party discovered a valley with steaming fumaroles they thought looked a lot like the Yellowstone Park area. They gave valley the picturesque name Valley of 10,000 Smokes. Today the pyroclastic flows with their steaming fumaroles have cooled leaving behind a valley filled with pyroclastic flows.
A Dutch Plane flying from Amsterdam to Japan was flying to Anchorage on its way to Japan when Redoubt Volcano erupted sending an ash cloud into the sky. The Dutch plane KLM flight 867 was heading for Anchorage, Alaska when it flew into the ash cloud at 27,900 feet. The engines shut down and the plane plunged toward the Talkeetna Mountains. The plane had dropped to 13,600 feet before the pilots were able to restart the engines five minutes later. The 231 passengers and fourteen crew members aboard the plane all landed safely.
Airplanes traveling from Europe and Asia to the United States often travel over remote islands in Alaska. Today there are more than 10,000 passengers and millions of dollars in air cargo that flies over Alaska each day. More than 15 planes have been damaged flying through ash clouds produced by Alaskan volcanoes since the near fatal flight of KLM flight 867 in 1989. Today the volcanoes in Alaska are constantly monitored so scientists alert pilots when an eruption has occurred and how they can avoid the ash clouds.
Redoubt volcano is an active volcano just 110 miles from Anchorage, Alaska. It has erupted four times since 1902. The 1989-1990 eruptions almost brought down KLM flight 867. The volcanic eruption was the first time scientists were able to predict an eruption by Bernard Chouet, a Swiss/American, called the long-period seismic events.
Redoubt volcano is part of the Aleutian volcanic arc of volcanoes that have formed due to the subduction of the Pacific Plate beneath the North American Plate. As the Pacific Plate melts it forms plutons of molten rock that collect in magma chambers before the volcano erupts.
The stratovolcano is a composite volcano that contains layers of pyroclastic flows and lava flows. The volcano has erupted andesite, basalt and dacite lavas during its eruptive past. Andesite has been the dominant lava produced in recent eruptions. It is considered one of the most dangerous volcanoes in Alaska because of its location near the Kenai Peninsula.
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