Spider Mountain
Spider Mountain is an 8,286-foot (2,526-metre) mountain summit located in the Glacier Peak Wilderness in western Chelan County of Washington state.[4] It is part of the North Cascades, which is a subset of the Cascade Range. Meltwater from the Spider Glacier on the steep north face, and other surface runoff from the mountain drains into Flat Creek, which is a tributary of the Stehekin River. The nearest higher neighbor is Mount Formidable 1.5 miles (2.4 km) to the west.[1] The Middle Cascade Glacier lies between these two mountains, and the Ptarmigan Traverse passes through also.
| Spider Mountain | |
|---|---|
 Spider Mountain from Maple Pass | |
| Highest point | |
| Elevation | 8,286 ft (2,526 m) [1] |
| Prominence | 926 ft (282 m) [1] |
| Parent peak | Mount Formidable (8,325 ft)[2] |
| Isolation | 1.33 mi (2.14 km) [2] |
| Coordinates | 48°24′34″N 121°02′10″W [1] |
| Geography | |
  Spider Mountain Washington, U.S.  Spider Mountain Spider Mountain (the United States) | |
| Parent range | North Cascades Cascade Range |
| Topo map | USGS Cascade Pass |
| Geology | |
| Type of rock | Schist |
| Climbing | |
| First ascent | 1938, Calder Bressler, Ralph Clough, Bill Cox, Tom Myers[3] |
| Easiest route | Scrambling Glacier travel |
Climate
Spider Mountain is located in the marine west coast climate zone of western North America.[3] Most weather fronts originate in the Pacific Ocean, and travel northeast toward the Cascade Mountains. As fronts approach the North Cascades, they are forced upward by the peaks of the Cascade Range, causing them to drop their moisture in the form of rain or snowfall onto the Cascades (Orographic lift). As a result, the west side of the North Cascades experiences high precipitation, especially during the winter months in the form of snowfall. During winter months, weather is usually cloudy, but, due to high pressure systems over the Pacific Ocean that intensify during summer months, there is often little or no cloud cover during the summer.[3] In terms of favorable weather, July through September are best for climbing.
Geology
The North Cascades features some of the most rugged topography in the Cascade Range with craggy peaks and ridges, deep glacial valleys, and granite spires. Geological events occurring many years ago created the diverse topography and drastic elevation changes over the Cascade Range leading to various climate differences.
The history of the formation of the Cascade Mountains dates back millions of years ago to the late Eocene Epoch.[5] With the North American Plate overriding the Pacific Plate, episodes of volcanic igneous activity persisted.[5] In addition, small fragments of the oceanic and continental lithosphere called terranes created the North Cascades about 50 million years ago.[5]
During the Pleistocene period dating back over two million years ago, glaciation advancing and retreating repeatedly scoured the landscape leaving deposits of rock debris.[5] The "U"-shaped cross section of the river valleys are a result of recent glaciation. Uplift and faulting in combination with glaciation have been the dominant processes which have created the tall peaks and deep valleys of the North Cascades area.
See also
- Geography of the North Cascades
- Geology of the Pacific Northwest
- List of highest mountain peaks in Washington
References
- "Spider Mountain, Washington". Peakbagger.com.
- "Spider Mountain - 8,300' WA". listsofjohn.com. Retrieved 2020-07-28.
- Beckey, Fred W. Cascade Alpine Guide, Climbing and High Routes. Seattle, WA: Mountaineers Books, 2008.
- "Spider Mountain". Geographic Names Information System. United States Geological Survey. Retrieved 2019-04-26.
- Kruckeberg, Arthur (1991). The Natural History of Puget Sound Country. University of Washington Press.
External links
- Spider Mountain weather: Mountain Forecast
- Spider Mountain photo: Flickr