Mount Rexford is a prominent mountain summit located in 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 the North Cascades, ...
of southwestern
British Columbia
British Columbia (commonly abbreviated as BC) is the westernmost Provinces and territories of Canada, province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include ...
,
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tota ...
. It is situated north of the
Canada–United States border
The border between Canada and the United States is the longest international border in the world. The terrestrial boundary (including boundaries in the Great Lakes, Atlantic, and Pacific coasts) is long. The land border has two sections: Can ...
, west of
Chilliwack Lake
Chilliwack Lake is a lake in the upper basin of the Chilliwack River southeast of the city of the same name in the Lower Mainland of British Columbia, Canada. The lake, while entirely within Canada, is located just north of the border between ...
, and east of
Slesse Mountain
Slesse Mountain, usually referred to as Mount Slesse, is a mountain just north of the US-Canada border, in the Cascade Mountains of British Columbia, near the town of Chilliwack. It is notable for its large, steep local relief. For example, its w ...
, which is its nearest higher neighbor.
Precipitation
runoff
Runoff, run-off or RUNOFF may refer to:
* RUNOFF, the first computer text-formatting program
* Runoff or run-off, another name for bleed, printing that lies beyond the edges to which a printed sheet is trimmed
* Runoff or run-off, a stock market ...
from the peak drains into Nesakwatch and Centre Creeks, both tributaries of the
Chilliwack River
Chilliwack ( )( hur, Ts'elxwéyeqw) is a city in the province of British Columbia, Canada. Chilliwack is surrounded by mountains and home to recreational areas such as Cultus Lake and Chilliwack Lake Provincial Parks. There are numerous outdoor ...
. Originally known as ''Ensawkwatch'', the mountain was named for an early settler in the area, Rexford, who had a cabin near Slesse Creek and had trap lines in the vicinity.
The mountain has two subsidiary peaks known as the Nesakwatch Spires. The mountain's name was officially adopted on June 2, 1950, by the
Geographical Names Board of Canada
The Geographical Names Board of Canada (GNBC) is a national committee with a secretariat in Natural Resources Canada, part of the Government of Canada, which authorizes the names used and name changes on official federal government maps of Can ...
.
Mount Rexford was first climbed in July 1951 by Herman Genschorek and Walt Sparling via the West Ridge.
Geology
Mount Rexford is composed of granitic rock related to the
Chilliwack batholith
The Chilliwack Batholith is a large batholith
A batholith () is a large mass of intrusive igneous rock (also called plutonic rock), larger than in area, that forms from cooled magma deep in Earth's crust. Batholiths are almost always made mo ...
, which intruded the region 26 to 29 million years ago after the major
orogenic
Orogeny is a mountain building process. An orogeny is an event that takes place at a convergent plate margin when plate motion compresses the margin. An ''orogenic belt'' or ''orogen'' develops as the compressed plate crumples and is uplifted ...
episodes in the region. This is part of the
Pemberton Volcanic Belt, an eroded
volcanic belt
A volcanic belt is a large volcanically active region. Other terms are used for smaller areas of activity, such as volcanic fields. Volcanic belts are found above zones of unusually high temperature () where magma is created by partial melting ...
that formed as a result of
subduction
Subduction is a geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries. Where the oceanic lithosphere of a tectonic plate converges with the less dense lithosphere of a second plate, ...
of the
Farallon Plate
The Farallon Plate was an ancient oceanic plate. It formed one of the three main plates of Panthalassa, alongside the Phoenix Plate and Izanagi Plate, which were connected by a triple junction. The Farallon Plate began subducting under the w ...
starting 29 million years ago.
Catalogue of Canadian volcanoes: Franklin Glacier
During the Pleistocene
The Pleistocene ( , often referred to as the '' Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed ...
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 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.
The North Cascades features some of the most rugged topography in the Cascade Range with craggy peaks and ridges, 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, and granite
Granite () is a coarse-grained ( phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies und ...
spires. Geological events occurring many years ago created the diverse topography and drastic elevation changes over the Cascade Range leading to various climate differences which lead to vegetation variety defining the ecoregion
An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas o ...
s in this area.
Climate
Based on the Köppen climate classification
The Köppen climate classification is one of the most widely used climate classification systems. It was first published by German-Russian climatologist Wladimir Köppen (1846–1940) in 1884, with several later modifications by Köppen, nota ...
, Mount Rexford is located in the marine west coast
An oceanic climate, also known as a marine climate, is the humid temperate climate sub-type in Köppen classification ''Cfb'', typical of west coasts in higher middle latitudes of continents, generally featuring cool summers and mild winters ...
climate zone of western North America. Most 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 ...
s originate in the Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contine ...
, and travel east toward the Cascade Range where they are forced upward by the 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. As a result, the Cascade Mountains experience high precipitation, especially during the winter months in the form of snowfall. Temperatures can drop below −20 °C with wind chill factors below −30 °C. The months July through September offer the most favorable weather for climbing Rexford.
Climbing Routes
Established rock climbing routes on Mount Rexford:[
* West Ridge - First Ascent 1951
* Northeast Ridge - FA 1969
* The Priest-Coupe (NE couloir) - FA 1970
* East Ridge - FA 1973
* South Ridge - FA 1981
* Southwest Flank -
* Southeast Arete -
]
See also
* Geography of British Columbia
British Columbia is the westernmost province of Canada, bordered by the Pacific Ocean. With an area of it is Canada's third-largest province. The province is almost four times the size of the United Kingdom and larger than every United States ...
* Geology of British Columbia
The geology of British Columbia is a function of its location on the leading edge of the North American continent. The mountainous physiography and the diversity of rock types and ages hint at the complex geology, which is still undergoing revi ...
References
External links
* Rexford's west face (aerial photo)
PBase
* Nesakwatch Spires Rock Climbing
Mountainproject.com
* Weather forecast
Mount Rexford
{{DEFAULTSORT:Rexford
Two-thousanders of British Columbia
Canadian Cascades
Pemberton Volcanic Belt
Cascade Range
North Cascades
Yale Division Yale Land District