Aleutian Range

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Aleutian Range
AKPen4.jpg
Alaska Peninsula, Peulik Volcano and Ukinrek Maars
Highest point
Peak Mount Redoubt
Elevation 10,197 ft (3,108 m)
Coordinates 60°29′07″N 152°44′35″W / 60.48528°N 152.74306°W / 60.48528; -152.74306
Dimensions
Length 600 mi (970 km)
Geography
Map of Alaska Peninsula Volcanoes.gif
Map showing volcanoes on the Alaska Peninsula
Country United States
State Alaska
Range coordinates 57°04′N 156°59′W / 57.07°N 156.99°W / 57.07; -156.99Coordinates: 57°04′N 156°59′W / 57.07°N 156.99°W / 57.07; -156.99
Borders on Tordrillo Mountains

The Aleutian Range is a major mountain range located in southwest Alaska, and it extends from Chakachamna Lake (80 miles/130 km southwest of Anchorage) to Unimak Island, which is at the tip of the Alaska Peninsula. It includes all of the mountains of the peninsula, and what makes it so special is its large number of active volcanoes, which are also part of the larger Aleutian Arc.[1] The mainland part of the range is about 600 miles (1000 km) long; the Aleutian Islands are (geologically) a partially submerged western extension of the range that stretches for another 1,600 km (1000 mi). However the official designation "Aleutian Range" includes only the mainland peaks and the peaks on Unimak Island.

The range is almost entirely roadless wilderness, and Katmai National Park and Preserve, a large national park within the range, must be reached by boat or plane.

Blockade Glacier in the Neacola Mountains

The core Aleutian Range can be divided into three mountain groups. Listed from southwest to northeast, they are:

See Aleutian Islands for the continuation of the range to the west of Unimak Island. Just to the north of the Aleutian Range are the Tordrillo Mountains, the southeasternmost extent of the Alaska Range.[2]

Aleutian Range

Selected mountains:

Volcanic Eruptions[edit]

Two volcanoes erupted during the summer of 2008 on the Eastern Aleutian Islands. On July 12, 2008, Mount Okmok erupted, and it continued to erupt for a month. A giant, rapidly moving ash and gas cloud shot up to a height of 15,240 m as a result of this eruption.[3] Mount Kasatochi was home to the other eruption, which occurred on August 7 and 8. This eruption also sent up a gas cloud about 15,000 high. Together, these two power volcanic eruptions deposited emissions of trace gases an aerosols into the atmosphere. These emissions formed a sulfate aerosol layer that totaled a transfer of 1.6 Tg of SO2 into the stratosphere and disturbed flights over this area for a short period following the eruptions.[4]

Earthquakes[edit]

In June 2014, a 7.9 magnitude earthquake struck the Aleutian Islands. The epicenter was below the earth's surface at a depth of 107 km.[5] The quake was caused by oblique normal faulting, and it occurred at a subduction zone. Here, the convergent boundary consists of the Pacific plate subducting underneath the North American plate, and this occurs at the speed of about 59 mm/year.[6] Although it was a powerful earthquake, no volcanic eruptions or tsunamis resulted, which is an unusual outcome since the area is seismically active.[7]

References[edit]

  1. ^ Cram 101 Textbooks (2014). Natural Hazards and Disasters: Earth sciences, Earth sciences. Cram 101. 
  2. ^ "GNIS Detail - Tordrillo Mountains". Retrieved 21 November 2012. 
  3. ^ "Explosive Eruption Of Okmok Volcano In Alaska". Science Daily. 21 July 2008. Retrieved 14 September 2016. 
  4. ^ Schmale; Schneider; Jurkat (January 27, 2010). "Aerosol layers from the 2008 eruptions of Mount Okmok and Mount Kasatochi; in situ upper troposphere and lower stratosphere measurements of sulfate and organics over Europe". Journal of Geophysical Research: Atmospheres. 115 (D2). Retrieved October 22, 2016. 
  5. ^ University of Portland (June 23, 2014). "Magnitude 7.9 ALEUTIAN ISLANDS, ALASKA" (PDF). iris.edu. Retrieved October 22, 2016. 
  6. ^ "Poster of the Aleutian Islands, Alaska Earthquake of 23 June 2014 - Magnitude 7.9". June 24, 2014. Retrieved October 22, 2016. 
  7. ^ Yulsman, Tom (23 July 2014). "Massive Earthquake Shakes Aleutian Islands". Discover Magazine. Retrieved 14 September 2016. 

External links[edit]