Luahna Peak
Geology
The North Cascades features some of the most rugged topography in the Cascade Range with craggy peaks, spires, ridges, and deep glacial valleys. 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. With the North American Plate overriding the Pacific Plate, episodes of volcanic igneous activity persisted. In addition, small fragments of the oceanic and continental lithosphere called terranes created the North Cascades about 50 million years ago.
During the Pleistocene period dating back over two million years ago, glaciation advancing and retreating repeatedly scoured the landscape leaving deposits of rock debris. The U-shaped cross section of the river valleys is 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.
Climate
Luahna Peak is located in the marine west coast climate zone of western North America. Weather fronts originating in the Pacific Ocean travel northeast toward the Cascade Mountains. As fronts approach the North Cascades, they are forced upward by the peaks (orographic lift), causing them to drop their moisture in the form of rain or snow onto the Cascades. As a result, Luahna Peak experiences high precipitation, especially during the winter months in the form of snowfall which feeds its glaciers. 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 with optimum weather for climbing Luahna from July through September.
Gallery
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Luahna Peak from High Pass. True summit and Pilz Glacier on left; Luahna's northwest summit (aka "Chalangin Peak") and Butterfly Glacier on right
See also
References
- ^ "Luahna Peak, Washington". Peakbagger.com. Retrieved April 17, 2019.
- ^ Beckey, Fred W. Cascade Alpine Guide, Climbing and High Routes. Seattle, WA: Mountaineers Books, 2008.
- ^ Kruckeberg, Arthur (1991). The Natural History of Puget Sound Country. University of Washington Press.