Bonanza Peak is a tall peak in 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 ...

in the

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its so ...

Washington Washington most commonly refers to: * George Washington (1732–1799), the first president of the United States * Washington (state), a state in the Pacific Northwest of the United States * Washington, D.C., the capital of the United States ** A ...

and the

Glacier Peak Wilderness Glacier Peak Wilderness is a , , wilderness area located within portions of Chelan County, Washington, Chelan, Snohomish County, Washington, Snohomish, and Skagit County, Washington, Skagit counties in the North Cascades of Washington (state), ...

of the

Wenatchee National Forest Wenatchee ( ) is the county seat and most populous city of Chelan County, Washington, United States. The population within the city limits in 2010 was 31,925, and has increased to 35,508 as of 2020. Located in the north-central part of the stat ...

. At in elevation, it is the highest point in Chelan County, and the highest non-volcanic peak in Washington. and the Cascade Range as a whole. Bonanza Peak's

prominence In topography, prominence or relative height (also referred to as autonomous height, and shoulder drop in US English, and drop in British English) measures the height of a mountain or hill's summit relative to the lowest contour line encircling ...

is , making it the 26th most prominent peak in Washington. The nearest higher peak is

Glacier Peak Glacier Peak or Dakobed (known in the Sauk-Suiattle dialect of the Lushootseed language as "Tda-ko-buh-ba" or "Takobia") is the most isolated of the five major stratovolcanoes (composite volcanoes) of the Cascade Volcanoes, Cascade Volcanic Arc ...

, to the southwest. Bonanza Peak is flanked with three large glaciers: Company Glacier to the north, Mary Green Glacier to the east, and Isella Glacier to the south.USGS topographic maps accessed from USGS

GNIS The Geographic Names Information System (GNIS) is a database of name and location information about more than two million physical and cultural features, encompassing the United States and its territories; the associated states of the Marshal ...

website

History

Bonanza Peak was originally named North Star Mountain, with a minor mountain to the southwest given the name Bonanza Peak. The USGS’ first topographic map of the region in 1904, however, mistakenly interchanged the names and the USGS naming was retained. Bonanza Peak was first summited in 1937 by Curtis I. James, Barrie James, and Joe Leuthold, all members of the

Mazamas The Mazamas () is a mountaineering organization based in Portland, Oregon, United States, founded in 1894. Promotion of mountaineering The Mazamas has been an important part of the climbing community in the Pacific Northwest of the United State ...

Climate

Lying east of the

Cascade Cascade, or Cascading may refer to: Science and technology Science * Air shower (physics), a cascade (particle shower) of subatomic particles and ionized nuclei ** Particle shower, a cascade of secondary particles produced as the result of a high ...

crest, the area around Bonanza Peak is a bit drier than areas to the west. Summers can bring warm temperatures and occasional thunderstorms.

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 The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as many of those in the ...

. As fronts approach the

, they are forced upward by the peaks (

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 North Cascades experiences high precipitation, especially during the winter months in the form of snowfall.Beckey, Fred W. Cascade Alpine Guide, Climbing and High Routes. Seattle, WA: Mountaineers Books, 2008. Precipitation runoff from the mountain and meltwater from its glaciers drains to nearby

Lake Chelan Lake Chelan ( ) is a narrow, long lake in Chelan County, north-central Washington state, U.S. It is an overdeepened lake and resembles a fjord, with an average width of . Near its upper end, the lake surface lies more than below peaks less t ...

via Agnes, Company, and Railroad Creeks.

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, 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. These climate differences lead to vegetation variety defining the

ecoregion An ecoregion (ecological region) is an ecological and geographic area that exists on multiple different levels, defined by type, quality, and quantity of environmental resources. Ecoregions cover relatively large areas of land or water, and c ...

s in this area. 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.

, a

stratovolcano A stratovolcano, also known as a composite volcano, is a typically conical volcano built up by many alternating layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with ...

that is southwest of Bonanza Peak, began forming in the mid-Pleistocene.Beckey, Fred W. Cascade Alpine Guide, Climbing and High Routes. Seattle, WA: Mountaineers Books, 2008. 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

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:Bonanza Peak from the trail between Lower and Upper Lyman Lake.jpg, Bonanza from Lyman Lakes area File:Plummer Mountain vista.jpg, Bonanza and North Star Mountain, from

Plummer Mountain Plummer Mountain is a prominent summit of the North Cascades, in Snohomish County of Washington state. It is located west of Suiattle Pass in the heart of the Glacier Peak Wilderness on land managed by Mount Baker-Snoqualmie National Forest. ...

File:Alpine Lakes Wilderness, Okanogan-Wenatchee National Forest (35532631143).jpg, Aerial view looking over the top of Martin Peak at Bonanza (right), and Glacier Peak.

References

External links