Monument Peak
is an mountain summit located in western
Okanogan County in
Washington state. It is part of the
Okanogan Range which is a sub-range of the
North Cascades. The mountain is situated in the
Pasayten Wilderness, on land administered by the
Okanogan–Wenatchee National Forest. The nearest higher peak is
Mount Lago, to the north.
[ Precipitation runoff from Monument Peak drains east into Monument Creek, and west into Eureka Creek, which are both part of the Methow River drainage basin. Topographic relief is significant as the summit rises above Eureka Creek in 1.25 mile (2 km).
]
Climate
Weather front
A weather front is a boundary separating air masses for which several characteristics differ, such as air density, wind, temperature, and humidity. Disturbed and unstable weather due to these differences often arises along the boundary. For ins ...
s originating in the Pacific Ocean travel northeast toward the Cascade Mountains. As fronts approach the North Cascades, they are forced upward by the peaks of the Cascade Range ( orographic lift), causing them to drop their moisture in the form of rain or snowfall onto the Cascades. 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.[Beckey, Fred W. Cascade Alpine Guide, Climbing and High Routes. Seattle, WA: Mountaineers Books, 2008.]
Geology
The North Cascades features some of the most rugged topography in the Cascade Range
The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington (state), Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as m ...
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 the various climate differences.
The history of the formation of the Cascade Mountains dates back millions of years ago to the late Eocene
The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...
Epoch.[ In addition, small fragments of the oceanic and ]continental lithosphere
A lithosphere () is the rigid, outermost rocky shell of a terrestrial planet or natural satellite. On Earth, it is composed of the crust and the lithospheric mantle, the topmost portion of the upper mantle that behaves elastically on time sc ...
called terrane
In geology, a terrane (; in full, a tectonostratigraphic terrane) is a crust fragment formed on a tectonic plate (or broken off from it) and accreted or " sutured" to crust lying on another plate. The crustal block or fragment preserves its d ...
s created the North Cascades about 50 million years ago.[
During the ]Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...
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.
]
Gallery
File:Blackcap and Monument from the lookout.jpg, Blackcap Mountain (left) and Monument Peak from Slate Peak
See also
* List of mountain peaks of Washington (state)
* Geography of the North Cascades
* Geology of the Pacific Northwest
References
{{reflist
External links
* Weather forecast
Monument Peak
* Monument Peak aerial photo
PBase
Okanagan Range
Mountains of Okanogan County, Washington
Two-thousanders of the United States