Copper Benchmark, also known as Copper Point, is a mountain summit located on the shared border between

Okanogan County Okanogan County () is a county located in the U.S. state of Washington along the Canada–U.S. border. As of the 2020 census, the population was 42,104. The county seat is Okanogan, while the most populous city is Omak. It is the largest c ...

and Chelan County in

Washington state Washington, officially the State of Washington, is a state in the Pacific Northwest region of the United States. It is often referred to as Washington State to distinguish it from the national capital, both named after George Washington ...

. Copper Benchmark is part of the Methow Mountains which are a subrange of the

North Cascades The North Cascades are a section of the Cascade Range of western North America. They span the border between the Provinces and territories of Canada, Canadian province of British Columbia and the U.S. state of Washington (state), Washington and ...

, and it is situated on the crest of 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 ...

between Kangaroo Pass and Copper Pass. It was used as a

triangulation station A triangulation station, also known as a trigonometrical point, and sometimes informally as a trig, is a fixed surveying station, used in geodetic surveying and other surveying projects in its vicinity. The station is usually set up by a map ...

for early surveying. It is protected by the Lake Chelan-Sawtooth Wilderness within the

Okanogan–Wenatchee National Forest The Okanogan–Wenatchee National Forest is a U.S. National Forest located in Okanogan County, Washington, Okanogan County in north-central Washington (state), Washington, United States. The forest is bordered on the north by British Columbia, ...

. Copper Benchmark has a subsidiary peak, '' Pica Peak'' (elevation , which is northwest of the summit. The nearest higher peak is Wallaby Peak, to the northeast. Precipitation runoff on the north side of the mountain drains to the

Methow River The Methow River ( ) is a tributary of the Columbia River in northern Washington in the United States. The river's watershed drains the eastern North Cascades, with a population of about 5,000 people. The Methow's watershed is characterized by ...

via Early Winters Creek, whereas the other sides of the mountain drain into tributaries of the Chelan River.

Climate

Copper Benchmark is located in the

marine west coast An oceanic climate, also known as a marine climate or maritime climate, is the temperate climate sub-type in Köppen classification represented as ''Cfb'', typical of west coasts in higher middle latitudes of continents, generally featuring co ...

climate zone of western North America.

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

, they are forced upward by the peaks of the Cascade Range (

orographic lift Orographic lift occurs when an air mass is forced from a low elevation to a higher elevation as it moves over rising terrain. As the air mass gains altitude it quickly cools down adiabatically, which can raise the relative humidity to 100% and cr ...

), 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. Because of maritime influence, snow tends to be wet and heavy, resulting in

avalanche An avalanche is a rapid flow of snow down a Grade (slope), slope, such as a hill or mountain. Avalanches can be triggered spontaneously, by factors such as increased precipitation or snowpack weakening, or by external means such as humans, othe ...

danger. During winter months, weather is usually cloudy. However, 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, p. 16

Geology

The North Cascades feature some of the most rugged topography in the

with craggy peaks, ridges, and deep

glacial valley U-shaped valleys, also called trough valleys or glacial troughs, are formed by the process of glaciation. They are characteristic of mountain glaciation in particular. They have a characteristic U shape in cross-section, with steep, straight s ...

s. 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. With the North American Plate overriding the Pacific Plate, episodes of volcanic igneous activity persisted. In addition, small fragments of the

oceanic Oceanic may refer to: *Of or relating to the ocean *Of or relating to Oceania **Oceanic climate **Oceanic languages **Oceanic person or people, also called "Pacific Islander(s)" Places * Oceanic, British Columbia, a settlement on Smith Island, ...

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:Copper Point seen from the North Cascades Highway.jpg, Copper Point, from North Cascades Highway File:Wallaby Peak summit view.jpeg, Copper Benchmark seen from Wallaby Peak

References

{{Portal bar, Geography, Geology, Mountains Mountains of Okanogan County, Washington Mountains of Chelan County, Washington North Cascades of Washington (state) Two-thousanders of the United States

Climate

Geology

Gallery

See also

References