Mount st. Helens
Mount st. Helens (to the indigenous cowlitz peoples it is know as the Lawetlat’la and to the klickitat it is know as the loowit) it is an active stratovolcano which is been located in skamania country, washington, in the united states in the pacific Northwest region. It is 154 km (that is 96 miles south of seattle, washington, and 80 km(50 miles) northeast of portland,Oregon.The Mount St. Helens got its name from the British diplomat Loard St Helen. The volcano is situated in the Cascade Range and is the part of the Cascade Volcanic Arc, a sement of the pacific Ring of Fire that includes over 160 active volcanoes .This volcano is mainly known by its ash explosions and pyroclastic flow. On may 18, 1980 in Mount St .Helens is most notorious for ifs catastrophic eruption which is the deadliest and most economically destructive volcanic event in the history of the united states. In this the 250 homes, 47 bridge, 15 miles (24 km) of railways, and 298 km (185 miles) of highways were destroyed, and Fifty-seven peoples were killed. A massive debris avalanche triggered by an earthquake measuring 5.1 on the Richter scale caused an eruption that reduced the elevation of the mountain’s summit from 2,950 m (9,677 ft ) to 2,550 m (8,365 ft ),replacing it with a 1.6 km (1 mile )wide horeshoe-shaped crater. The Mount St. Helens National Volcanic Monument was orginated for the presuring of volcano and also for its aftermath to be scientifically studied. The debris avalanche was up to 2.9 km cub (0.7 cubic miles ) in volume. In the cascade Range, Mount St. Helen is a large eruptive cone consisting of lava rock inter layered with ash, pumice and with also other deposits. The basalt and andestie includes layers of mountain through which the several domes of dacite lava have erupted. The Mount St. Helens is 72 km (45 miles ) west of the Mount Adams, which is in the western part of the Cascade range. These two mountains which can be said as the “sister and brother”volcanic mountains are approximately 80 km (50 miles) from the Mount Rainier, the highest of Cascade volcanoes. The Mount Hood, the nearest major volcanic peak in Oregon is 100 km (60 miles) Southeast of Mount St. Helens. When we compare the Mount St. Helens with the other major Cascade volcanoes it is geologically young compared with the other major Cascade volcanoes. It formed only within the past 40,000 years and the pre-1980 summit cone began rising about 2,200 years ago. This volcano is considered the most active in the Cascades with the Holocene epoch. The Mount St. Helens was the fifth-highest peak in Washington. It got the nick name Fuji-san of America because it stood out prominently from surrounding hills because of the symmetry and extensive snow and ice cover of the pre-1980 summit cone. The peak rose more than 1,500 m about 5,000 feet above its base, where as the lower flanks merge with adjacent ridges. The mountain is 9.7 km about 6 miles across at its base, which is at an altitude of 4,400 feet ( 1,300 m) on the northeastern side and 1,200m about 4,000 feet. And at the pre-eruption tree line, the width of the cone was 6.4 km that is 4 miles. The streams that originate on the volcano enter into three main river systems they are the Toutle River on the north and northwest, the Kalama River on the west and the Lewis River on the south and east. The streams are fed by abundant rain and snow. The average annual rainfall is 140 inches (3,600 mm), and the snow pack on the mountain’s upper slopes can reaches 4.9 m (16 feet).For the hydroelectric power generation the Lewis River is impounded by the three dams. The southern and eastern sides of the volcano drain into an upstream impoundment, the swift Reservoir, which is directly south of the volcano’s peak. Although Mount St. Helens is in Skamania Country, Washington, access routes to the mountain run through Cowlitz Country to the west state, locally known as the Spirit lake Memorial Highway, connects with interstate 5 at 34 miles (55 km)to the west of the mountain. The community nearest the volcano is cougar, Washington, in the Lewis River valley 11 miles (18 km) south- southwest of the peak. The Gifford Pinchot National Forest surrounds the Mount St. Helens.
Facts Of Mount St. Helen
Mount st. Helens (to the indigenous cowlitz peoples it is know as the Lawetlat’la and to the klickitat it is know as the loowit) it is an active stratovolcano which is been located in skamania country, washington, in the united states in the pacific Northwest region. It is 154 km (that is 96 miles south of seattle, washington, and 80 km(50 miles) northeast of portland,Oregon.The Mount St. Helens got its name from the British diplomat Loard St Helen. The volcano is situated in the Cascade Range and is the part of the Cascade Volcanic Arc, a sement of the pacific Ring of Fire that includes over 160 active volcanoes .This volcano is mainly known by its ash explosions and pyroclastic flow. On may 18, 1980 in Mount St .Helens is most notorious for ifs catastrophic eruption which is the deadliest and most economically destructive volcanic event in the history of the united states. In this the 250 homes, 47 bridge, 15 miles (24 km) of railways, and 298 km (185 miles) of highways were destroyed, and Fifty-seven peoples were killed. A massive debris avalanche triggered by an earthquake measuring 5.1 on the Richter scale caused an eruption that reduced the elevation of the mountain’s summit from 2,950 m (9,677 ft ) to 2,550 m (8,365 ft ),replacing it with a 1.6 km (1 mile )wide horeshoe-shaped crater. The Mount St. Helens National Volcanic Monument was orginated for the presuring of volcano and also for its aftermath to be scientifically studied. The debris avalanche was up to 2.9 km cub (0.7 cubic miles ) in volume. In the cascade Range, Mount St. Helen is a large eruptive cone consisting of lava rock inter layered with ash, pumice and with also other deposits. The basalt and andestie includes layers of mountain through which the several domes of dacite lava have erupted. The Mount St. Helens is 72 km (45 miles ) west of the Mount Adams, which is in the western part of the Cascade range. These two mountains which can be said as the “sister and brother”volcanic mountains are approximately 80 km (50 miles) from the Mount Rainier, the highest of Cascade volcanoes. The Mount Hood, the nearest major volcanic peak in Oregon is 100 km (60 miles) Southeast of Mount St. Helens. When we compare the Mount St. Helens with the other major Cascade volcanoes it is geologically young compared with the other major Cascade volcanoes. It formed only within the past 40,000 years and the pre-1980 summit cone began rising about 2,200 years ago. This volcano is considered the most active in the Cascades with the Holocene epoch. The Mount St. Helens was the fifth-highest peak in Washington. It got the nick name Fuji-san of America because it stood out prominently from surrounding hills because of the symmetry and extensive snow and ice cover of the pre-1980 summit cone. The peak rose more than 1,500 m about 5,000 feet above its base, where as the lower flanks merge with adjacent ridges. The mountain is 9.7 km about 6 miles across at its base, which is at an altitude of 4,400 feet ( 1,300 m) on the northeastern side and 1,200m about 4,000 feet. And at the pre-eruption tree line, the width of the cone was 6.4 km that is 4 miles. The streams that originate on the volcano enter into three main river systems they are the Toutle River on the north and northwest, the Kalama River on the west and the Lewis River on the south and east. The streams are fed by abundant rain and snow. The average annual rainfall is 140 inches (3,600 mm), and the snow pack on the mountain’s upper slopes can reaches 4.9 m (16 feet).For the hydroelectric power generation the Lewis River is impounded by the three dams. The southern and eastern sides of the volcano drain into an upstream impoundment, the swift Reservoir, which is directly south of the volcano’s peak. Although Mount St. Helens is in Skamania Country, Washington, access routes to the mountain run through Cowlitz Country to the west state, locally known as the Spirit lake Memorial Highway, connects with interstate 5 at 34 miles (55 km)to the west of the mountain. The community nearest the volcano is cougar, Washington, in the Lewis River valley 11 miles (18 km) south- southwest of the peak. The Gifford Pinchot National Forest surrounds the Mount St. Helens.
Facts Of Mount St. Helen
- Location : Skamania Country, Washington, United States
- Range :Cascade Range
- Coordinates : 46 degree 11' 28"N 122 degree 11'40"W
- Type : Active stratovolcano
- Age of Rock : < 40,000 years
- Volcanic Arc : Cascade Volcanic Arc
- First Ascent : Thomas J. Dryer in 1853
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