The maximum height of the cordillera mountain. Mountains in North America. Andes in South America on the map

), which occupies the west of North America and extends within the US proper and Alaska, Canada and Mexico. The total length is more than 7 thousand km. km(from 19°N to 69°N). The width of the mountain belt in Alaska reaches 1100-1200 km, in Canada - up to 800 km, on the territory of the United States proper - about 1600 km, in Mexico - up to 1000 km. The southern boundary of K. S. A. is the tectonic depression of the valley of the river. Balsas, separating North and Central America.

Orography. Three longitudinal belts are distinctly expressed in K. S. A. - eastern, inner and western. The eastern belt, or the belt of the Rocky Mountains, is represented by a chain of high massive ridges, for the most part serving as a watershed between the basin Pacific Ocean and the basins of the Gulf of Mexico and the North Arctic Ocean. In the east, the belt abruptly breaks off to foothill plateaus (Arctic, Great Plains); in the west, it is limited in places by deep tectonic depressions (the "Moat of the Rocky Mountains") or valleys. major rivers(Rio Grande), and in some places gradually turns into mountain ranges and plateaus. In Alaska, the Brooks Range belongs to the Rocky Mountain belt; in northwestern Canada, the Richardson Range and the Mackenzie Mountains, bounded in the north and south by the through valleys of the Peel and Liard rivers.

To the south, on the territory of Canada and the USA, up to 32 ° N. sh., the Rocky Mountains proper stretch. Between 45° N. sh. and 32° N. sh. the eastern belt reaches its greatest width and is represented by isolated high (over 4000 m), but small along the ridges and massifs, separated by vast sections of the plateau (“parks”): Savatch Massif, San Juan Mountains, Front Range, Yuinta Mountains. In the area between 32° and 26° N. sh., cut by the valley of the river. The Rio Grande, the belt is indistinct: the mountain ranges are separated by sections of plateaus and basins, which merge in the west with the Bolsons of the Mexican Highlands, and in the east they pass into the Eduarde Plateau. The southernmost segment of the eastern belt forms the Eastern Sierra Madre (height up to 4054 m).

The inner belt of K. S. A., or the belt of internal plateaus and uplands, is enclosed between the eastern belt and the belt of the Pacific ridges in the west. In inner Alaska, it includes vast tectonic depressions occupied by river valleys and alternating with flat-topped mountain ranges up to 1500- 1700 m(mountains Kilbak, Kuskokwim, Ray); in Canada - numerous high plateaus (Yukon, Stikine, Fraser), mountain ranges and ranges that are not inferior in height to the ranges of the Rocky Mountains (Cassiar-Omineka Mountains, 2590 m; Columbian mountains, before 3581 m); within the US and Mexico proper - high-altitude massifs in the area of ​​batholith development in the state of Idaho (height up to 3857 m), the Snake and Columbia Volcanic Plateaus (average heights up to 1000 m), the Great Basin Plateau and northeastern Mexico, as well as the Colorado Plateau and the Mexican Highlands.

The western belt consists of a belt of Pacific ridges, a belt of intermountain depressions, and a belt of coastal chains. The belt of the Pacific ridges, bordering the inner region of K. S. A. from 3., includes the highest ridges of the mountain system, including the Alaska Range with the highest point of the entire mainland - Mount McKinley (6193 m), chain of volcanic Aleutian Islands, Aleutian Range (Iliamna Volcano, 3075 m), alpine node of the massif of St. Elias (Logan, 6050 m), a heavily dissected Coast Range (Waddington, 4042 m), forming a characteristic fjord coast along its entire length. On the territory of the United States and Mexico proper, this belt includes the Cascade Mountains with a series of peaks-volcanoes (Volcano Rainier, 4392 m), Sierra Nevada Range (Whitney, 4418 m), ridges of the California Peninsula (heights up to 3078 m), separated from the inner belt by the depression of the Gulf of California, the Transverse Volcanic Sierra with Orizaba volcanoes (5700 m), Popocatepetl (5452 m), Nevado de Colima (4265 m). Intermontane longitudinal depressions are represented both by sea inlets and straits (Cook Bay, Shelikhov Straits, Georgia, Sebastian-Viscaino Bay), and a series of lowlands and plateaus (Susitna Lowland, Copper River Plateau, Willamette Valley, Great California Valley). The belt of coastal chains, bordering the western edge of the mainland, is the most fragmented part of the K. S. A. mountain structure, represented by low and medium-altitude ridges (US Coast Ranges, Sierra Vizcaino on the California Peninsula) and a series of mountainous offshore islands(Kodiak Islands, Queen Charlotte, Vancouver, Alexander Archipelago). highest height this belt reaches south of Alaska, in the Chugach mountains (Marques-Baker, 4016 m).

Geological structure and minerals. K. S. A. are formed by different tectonic elements. In the south of the USA, the raised latest movements the western part of the Precambrian North American Platform (the Colorado Plateau and the eastern ridges of the Rocky Mountains), where the folded basement (absolute age about 2.4 billion years) is overlain by the Paleozoic and Mesozoic horizontal mantle. To the west, the myo- and eugeosynclinal troughs of the mesozoids of the Sierra Nevada and the Rocky Mountains (Nevadids) stretch. In Canada, the mesozoids are separated from the platform by the Cis-Cordillera marginal foredeep, filled with carbonate and saline formations of the Middle Paleozoic and molasses of the Jurassic and Lower Cretaceous, and in Alaska - from the ancient Yukon massif - by the Tintin deep fault. Similar faults separate the Mesozoic of Mexico from the Precambrian Central American massif. The formation of geosynclinal troughs of the Nevadids took place in the Late Precambrian, and the accumulation of sediments in them continued until the end of the Jurassic. Carbonate (Paleozoic) and terrigenous (Mesozoic) strata of the miogeosyncline up to 10 km. The eugeosyncline is composed of volcanogenic and volcanogenic-sedimentary strata about 15 km. In the Late Jurassic, the mesozoites of Canada and the United States were folded, and in the Early Cretaceous, granitoids were intruded into them. Within the Western Sierra Madre and the California Peninsula, folded and orogenic processes occurred in the Late Cretaceous - Paleocene time (laramides), and the introduction of granites dates back to the Late Cretaceous - Oligocene.

To the west of the Mesozoic, on the Alaska Peninsula and in the Coast Ranges of California and Oregon, as well as in southern Central America, the Cenozoic geosynclinal system extends. It is composed of powerful (up to 25 km) strata of volcanogenic and sedimentary rocks of the Upper Jurassic, Cretaceous and Cenozoic. These areas are characterized by volcanism, high seismicity and intense modern tectonic movements. In the north of the Pacific Ocean, geosyncline structures include the Aleutian Trench, and in the south, the Central American Deep Trench; the formation of a deep trough in the Gulf of California is associated with the development of the geosyncline.

In the Cis-Cordillera foredeep (Canada) and in young depressions (Alaska, California) there are oil deposits, in the mesozoids of the Rocky Mountains, Sierra Nevada and Sierra Madre - ores of gold, tungsten, copper, molybdenum (see Climax) , polymetals, in the Cenozoic structures of the Coast Ranges - mercury, as well as coal, etc.

N. A. Bogdanov.

Relief. The eastern belt is characterized by both large arched massifs dissected by river valleys (the Brooks Range, the Mackenzie Mountains, the Rocky Mountains of Canada and the Eastern Sierra Madre) and short anticlinal ridges formed in the area of ​​marginal platform structures (the Rocky Mountains of the United States).

In the relief of the inner belt, high plateaus (Yukon, Stikine, and others) stand out, which are a combination of large flat-topped massifs and wide basins crossed by river valleys; lava plateaus (Fraser, Columbia, Mexico), deeply cut by river canyons; half-buried highlands ( Big Pool), which have a folded base brought to the surface in the form of short numerous ridges surrounded by extensive depressions, as well as deeply dissected plateaus (the Colorado Plateau, etc.), which are a site of platform structures involved in the Cordillera mountain belt.

The belt of Pacific ridges is characterized by large anticline ridges with outcrops of intrusive rocks in the axial part (Alaska Range); close to this type are the massive batholith ridges of considerable length (the Sierra Nevada, the Coastal Range). Another type is volcanic ridges, which have a folded base, complicated by a series of volcanoes planted on it, including active ones. In the belt of longitudinal depressions, accumulative lowlands (Great California Valley) have become widely developed. The belt of coastal chains is most characterized by low, weakly dissected ridges that form rectilinear coasts.

In the northern part of K. S. A. (to the north of 40-49 ° N. latitude), both ancient glacial (troughs, cirques, terminal moraine ridges, loess, outwash and lacustrine plains) and modern nival landforms (kurums , upland terraces, etc.), confined to the highest levels of mountains (Alaska Range, Rocky Mountains). In areas not subjected to glaciation (inner Alaska), thermokarst and polygonal landforms associated with the distribution of rocks and soils. In the rest of the C. S. A., water-erosion forms predominate: valley dissection in the most humid regions (Canadian Cordillera), table forms and canyons in arid regions (Colorado and Columbia Plateaus). Desert regions (Great Basin, Mexican Highlands) are characterized by denudation and eolian forms.

Climate. The northern part of K. S. A. is located in the arctic (Brooks Ridge) and subarctic (most of Alaska) belts, the territory up to 40 ° N. sh. - V temperate zone, to the south - in the subtropical, the California Peninsula and the Mexican Highlands - in the tropical. On the slopes facing the Pacific Ocean, the climate is predominantly mild, oceanic (at the latitude of San Francisco - Mediterranean), in the interior - continental. On the Yukon Plateau, the average January temperature is about -30 ° C, July 15 ° C. In the Great Basin, winter temperatures drop to -17°C, while summer temperatures often exceed 40°C (the absolute maximum is 57°C). In July, the highest temperatures are observed in the intermountain valleys of the South (32 °С in the lower reaches of the Colorado River), the lowest - in the highlands of South Alaska (8 °С in the Chugach Mountains and the St. Ilya massif). Humidification is extremely uneven. In the temperate zone, the extreme west is best moistened; in the tropical zone, the extreme east. The inner plateaus receive the least amount of precipitation. On the southern ranges of Alaska, the annual precipitation is 3000-4000 mm, on the coast British Columbia- up to 2500 mm, on the US internal plateau, it drops to 400-200 mm. The Mojave Desert receives only 50 rainfall. mm in year. To the south-east Mexican highlands rainfall increases to 2000 mm. The greatest thickness of the snow cover (up to 150 cm and more) is observed in the south of Alaska (mountains Chugach, St. Ilya, Wrangel), as well as on the Coast Range and in Columbian mountains Canada.

Glaciation. Large differences in the latitudinal and altitudinal position of the K. S. A., as well as a sharp difference in the moistening of the territory, have led to the uneven development of modern glaciation. The lowest (300-450 m) the snow line is located on the Pacific slope of the mountains of South Alaska, in some places descending to the level of the ocean. On the northern slopes of the Chugach and St. Ilya mountains, the snow limit is at an altitude of 1800-1900 m, on the Alaska Range - from 1350-1500 m(southern slope) up to 2250-2400 m(northern slope). The area of ​​present-day glaciation here reaches 52,000 sq. km 2. In the Brooks Range and the Mackenzie Mountains, glaciation is developed only at the highest peaks. To the south, the snow line rises to 1500-1800 m in the Coast Range and up to 2250 m - in the Columbian Mountains of Canada. As a result, the glaciation area of ​​inland Alaska and the Canadian Cordillera is only 15,000 km2. km 2. On the territory of the United States proper, the snow limit rises to 2500-3000 m in the Cascades and Rockies, up to 4000 m more than - in the Sierra Nevada, up to 4500 m and more - in Mexico. The area of ​​modern glaciation in the United States is estimated at 0.5-0.6 thousand km2. km 2, in Mexico - 0.011 thousand km 2. All the main types of glaciers are represented in K. S. A.: vast ice fields and caps, washed by glaciers (Depont glacier in the Coast Range), foothill glaciers, or foot glaciers (Malaspina), valley glaciers (Hubbard, length 145 km in the Coast Range), cirque and short hanging glaciers, mostly disappearing (Sierra Nevada). On the volcanic peaks, star-shaped glaciers form, sending numerous glacial flows from themselves (there are more than 40 flows on the Rainier volcano).

Rivers and lakes. Within C.S.A. lie the origins of many river systems mainland: Yukon, Peace River - Mackenzie, Saskatchewan - Nelson, Missouri - Mississippi, Colorado, Columbia, Fraser. Since the main watershed is the eastern belt of mountains, most of the precipitation that falls within the boundaries of the K. S. A. flows to the west, into the Pacific Ocean. North of 45-50° N. sh. on the Pacific coast, the rivers are fed mainly by snow with a pronounced spring flood. In the south, rainfall predominates, with a winter maximum on the Pacific coast and a spring and summer maximum in inland regions. In the southern part of the K. S. A., significant territories do not have a runoff into the ocean and are irrigated mainly by short-term streams ending in drainless salt lakes(the largest of them is the Great Salt Lake). Numerous in the north freshwater lakes glacial-tectonic and dam origin (Atlin, Kootenay, Okanagan, etc.)

The most full-flowing mountain rivers, having a large fall and being regulated by lakes, have a huge hydropower potential and are widely used for electricity generation and irrigation. On the river Columbia, more than 10 sites suitable for the construction of hydroelectric power stations have been identified, and some of them have already been used (Grand Coulee, Te Dals, etc.).

natural areas. Due to the considerable height along the entire length of the K. S. A., altitudinal zonation is clearly expressed natural landscapes. At the same time, the stretching of mountain ranges in the direction perpendicular to the main flow of moisture causes significant differences between the landscapes of the coastal (Pacific) and inland parts of the territory. The biggest changes in landscapes are associated with the latitudinal position of the mountain system, with its transition from the subarctic zone to the temperate, subtropical and tropical. There are 4 main natural regions: the Northwest, the Canadian Cordillera, the US Cordillera and the Mexican Cordillera.

The northwestern region, or the Alaska Cordillera, covers most of the state of Alaska and the Yukon Plateau in northwestern Canada. Alpine ranges with extensive glaciation predominate in the south, while plateaus dominate the rest of the territory. The climate is subarctic, south coast- moderate. With the exception of the coast of the Gulf of Alaska, permafrost is developed everywhere. The spectrum of altitudinal belts is represented by foothill woodlands (forest tundra) in river valleys and mountain tundra on high plateaus. Subarctic meadows are developed on the western coast, on the southern Pacific slopes - belts of tall coniferous forests of hemlock and arborvitae (the so-called coastal forest), subalpine light forests, replaced at the peaks by alpine meadows and glaciers. Reindeer, arctic foxes, polar hares, lemmings live in the tundra. Elk, grizzly bear, wolf, fox and other predators are found in the forests. Lots of birds. The bulk of the population and cities are concentrated on the south coast.

Canadian Cordillera - the narrowest part of the mountain belt, including southeast coast Alaska and partly entering the territory of the USA (up to 44 ° N). The relief is dominated by high mountain ranges with a wide development of ancient glacial forms and modern glaciation. The climate is temperate, from humid to dry. The range of vertical belts includes steppes on the bottoms of intermountain valleys, pine forest-steppe on high plateaus, mountain coniferous forests from fir, spruce, red cedar, balsam pine on slopes where podzolic brown forest and mountain forest soils are developed, subalpine coniferous woodlands and alpine meadows on mountain meadow and skeletal soils in the summit part. The Pacific slopes are occupied by tall forests of Douglas, Sitka spruce, hemlock and arborvitae, coming here from southern regions Alaska. There are many different animals in the mountain forests: wapiti reindeer, moose, caribou, grizzly bear; there are wolf, fox, wolverine, lynx, puma, mountain sheep. Fur-bearing animals include marten, ermine, mink, coypu, and muskrat. The population is concentrated mainly in the south, in coastal cities (Vancouver). The steppe lands of the valleys are cultivated, the forest-steppe plateaus are used as pastures.

The US Cordillera, or the Southern Cordillera, correspond to the widest part of the mountain belt and have a wide variety of natural conditions. High wooded ridges, covered with snowfields and glaciers, directly adjoin here to vast drainless desert plateaus. The climate is subtropical, Mediterranean on the coast, arid in the interior. On the slopes of high ridges (Forward Range, Sierra Nevada), mountain belts are developed. pine forests(American spruce, larch), coniferous subalpine woodlands and alpine meadows. The low Coast Ranges are covered with mountain pine forests, groves of relict redwood forests and evergreen hard-leaved shrubs (chaparral). The western slopes of this part of the Cordillera are rich in forest resources, but in the 19th and especially in the 20th centuries. forests were severely cut down and suffered from frequent fires, and the area under them was significantly reduced (Sitka spruce, Douglas, etc., which survived in small numbers on the Pacific coast, were especially affected). Vast areas of the inner plateau are occupied by sagebrush and shrubby semi-deserts and deserts, low ridges are occupied by pine and pine-juniper woodlands. In the lands developed by man, large animals are either destroyed or are on the verge of destruction. The bison are almost completely exterminated, the pronghorn antelope is rare. Rich animal world preserved only in reserves (Yellowstone National Park, Yosemite National Park, etc.). In semi-desert areas, rodents, snakes, lizards, and scorpions are predominantly distributed. The population is concentrated near the Pacific coast, where big cities(Los Angeles, San Francisco). In the river valleys - arrays of irrigated lands used for subtropical fruit crops. Subtropical woodlands and scrub deserts are used as pastures.

Mexican Cordilleras. Includes the Mexican Highlands and the California Peninsula. The relief is dominated by high plateaus and uplands, strongly dissected in places (Western Sierra Madre). High seismicity is characteristic. The climate is tropical, mostly dry. On the windward slopes, low-growing thorny forests (at the foot) and deciduous tropical forests (at the peaks) are developed. In the inner parts, shrubby creosote and high-altitude succulent deserts, cactus-acacia savannas and mountain coniferous-hard-leaved forests are common. Of the animals in the deserts and semi-deserts, there are puma, pronghorn antelope, meadow wolf, or coyote, many hares, voles, and other rodents. The forests are inhabited by black bears, lynxes, and other predators. Monkeys, tapirs, jaguars are found in tropical forests. Most of the population is concentrated on the Central Mesa plateau, where the main cities of Mexico (Mexico City, Guadalajara, San Luis Potosi) are located, and on the coast of the Gulf of Mexico (ports of Tampico, Veracruz). Significant tracts of land in the south are used for plantations of tropical crops and grain crops.

Lit.: Ignatiev G. M., North America, M., 1965; Relief of the Earth, M., 1967; Vitvitsky G.N., Climates of North America, M., 1953; King F. B., Geological development of North America, trans. from English, M., 1961; Bostock, H. S., Physiography of the Canadian Cordillera, Ottawa, 1948; Landscapes of Alaska, Los Ang., 1958; Tamayo J. L., Geografia general de Mexico, 2 ed., v. 1-4, Mex., 1962; Thornbury W. D., Regional geomorphology of the United States, N. Y., 1965.

A. V. Antipova, G. M. Ignatiev.

Cordillera, the largest mountain system the globe, stretching along the western margins of North and South America, from 66 ° N.S. (Alaska) to 56°S sh. (Tierra del Fuego).

The length is more than 18 thousand km, the width is up to 1600 km in North America and up to 900 km in South America. Located in [Canada, USA, Mexico, Central America, Venezuela, Colombia, Ecuador, Peru, Bolivia, Argentina and Chile.

Almost along its entire length, it is a watershed between the basins of the Atlantic and Pacific oceans, as well as a pronounced climatic boundary. In height they are second only to the Himalayas and the mountain systems of Central Asia. The highest peaks of the Cordillera: in North America - Mount McKinley (6193 m), in South America - Mount Aconcagua (6960 m).

The entire Cordillera system is divided into 2 parts - Cordillera of North America, and the Cordillera of South America, or the Andes.

The main mountain-building processes that resulted in the emergence of the Cordillera began in North America in the Jurassic, in South America at the end of the Cretaceous and took place in close connection with the formation of mountain systems on other continents (Alpine folding). The formation of the Cordillera has not yet ended, as evidenced by frequent earthquakes and intense volcanism (more than 80 active volcanoes). An important role in the formation of the relief of the Cordillera was also played by the Quaternary glaciation, especially north of 44° N. latitude. and south of 40°S.

The Cordilleras lie in all geographic zones (except for the subantarctic and antarctic) and are distinguished by a wide variety of landscapes and a pronounced altitudinal zonality. The snow limit in Alaska is at an altitude of 600 m, in Tierra del Fuego - 500-700 m in Bolivia and South Peru rises to 6000-6500 m. In the northwestern part of the Cordilleras of North America and in the southeast of the Andes, glaciers descend to ocean level in the hot zone they cover only the highest peaks. total area glaciations - about 90 thousand km 2 (in the Cordillera of North America - 67 thousand km 2, in the Andes - about 20 tons km 2).

Literature

• Geographic encyclopedic dictionary, M., 1986.

The Cordillera of North America is the northern part of the Cordillera mountain system, stretching along Pacific coast mainland for nine thousand kilometers, and diverging in width for more than one and a half thousand kilometers. They start on, their southern border is the valley of the Mexican Balsas River, which separates North and Central America, to the south - the mountains of the Southern Sierra Madre, belonging to the Cordillera of Central America, which pass into the Andes, forming the longest mountain system of the Earth with a length of more than 18 thousand km .
These mountains cross the territory of three countries of North America: the USA (from Alaska to California), Canada and Mexico.
The history of the formation of the Cordilleras of North America is incredibly complex, primarily because of the large area of ​​​​this object and the significant duration of its formation: for example, the age of the rocks of the vast Colorado Plateau and the eastern ridges of the Rocky Mountains is about 2.4 billion years. The process of formation of the Cordilleras of North America is still in its active phase, earthquakes are not uncommon here, and volcanic eruptions also occur.
In the configuration of this part of the Cordillera, three longitudinal mountain belts are clearly visible.
East, he is a belt with the top of Elbert, - a chain of high massive ridges. In the east, it is bounded by a sharp ledge, which is the boundary of the foothill plateaus (Arctic Plateau, Great Plains), and in the west it is bounded by deep tectonic depressions, called the "Moat of the Rocky Mountains", or by the valleys of large rivers like the Rio Grande. The southernmost section of the eastern belt forms the Eastern Sierra Madre, about 4 km high.
The inner belt is enclosed between the eastern belt and the western belt of the Pacific ridges. In Alaska, these are vast tectonic depressions occupied by river valleys and alternating with relatively low mountain ranges, in Canada - numerous high plateaus under 2.5 km high, within the US and Mexico proper - high mountain ranges and volcanic plateaus.
The western (Pacific) belt, which includes the highest ridges, consists of a belt of Pacific ridges, a belt of intermountain depressions, and a belt of coastal chains. The belt of the Pacific ridges includes the Alaska Range with the highest point of the entire mainland - the top of Denali. Part of the western belt are large mountains- Cascading, Sierra Nevada Range and Transverse Volcanic Sierra. Most of the peaks of the local mountains are cones of active and extinct volcanoes height of 4 km and above, the most famous are Rainier, Orizaba, Popocatepetl and Nevada de Colima.
In the lows between mountain ranges sedimentary rocks accumulated for a long time, as a result, huge deposits of various minerals were formed throughout the Cordillera of North America, and metal ores were formed in the thickness of the mountains. There are oil deposits in the Canadian Cis-Cordillera foredeep and in depressions in Alaska and California, in the Rocky Mountains, Sierra Nevada and Sierra Madre - ores of gold, tungsten, copper, molybdenum, polymetals, in the Coast Ranges - mercury and everywhere - deposits of stone coal.
Glaciers occupy almost 70 thousand km 2, most of which are located in the mountains of Alaska, among them Bering stands out - the largest mountain glacier in North America (some glaciologists believe that the whole world).
In the Cordillera lie the sources and headwaters of many major rivers in North America: Yukon, Saskatchewan, Missouri, Columbia, Colorado, Rio Grande. There are lakes, many are salty, the most famous is Bolshoe Salt.
The Cordillera of North America is the northern part of the Cordillera mountain system, stretching along western outskirts North America and Central America.
The length of the Cordillera of North America is great, this explains the noticeable difference in landscapes - depending on the latitudinal position of the mountain system.
The natural landscapes of the Cordilleras of North America throughout their length, due to their considerable height, have a pronounced altitudinal zonality, which is largely typical of such large mountainous regions.
The division of the Cordillera zone of North America into four main natural regions is accepted: the Northwest, the Canadian Cordillera, the US Cordillera and the Mexican Cordillera.
The northwestern (Alaskan Cordillera) occupies most of the American and Canadian Yukon plateaus. Here is the kingdom of high mountain ranges with powerful glaciation, the climate is from arctic to temperate. Vegetation is poor, as permafrost is everywhere. On the slopes of the mountains - mountain tundra, and above - glaciers, in the valleys of freezing rivers - forest tundra, on the western coast - warmer - subarctic meadows and coastal coniferous forests appear. Reindeer, arctic fox, polar hare, lemming live in the tundra. The forest is the habitat of the grizzly bear, wolf, fox. A lot of birds.
People settled only on the coast, where all the cities and towns are located.
The population is engaged in fishing, hunting for fur-bearing animals and the extraction of the most valuable minerals (gold, oil), since the export of others is too expensive.
The Canadian Cordillera, partly entering the territory of the United States, is the narrowest part of the mountain belt. There are many mountain ranges and glaciers, but the climate is milder - temperate, humid. Steppes appear in the river valleys, and thickets of mountain coniferous forests appear on the plateau: fir, spruce, red cedar, balsam pine. The animal world becomes more diverse, the moose, wolverine, lynx, cougar, mountain sheep, fur-bearing animal appear: marten, ermine, mink, nutria, muskrat.
The local population is the inhabitants of large port cities like Vancouver, as well as farmers: the steppes are plowed up, the forest-steppe plateaus are used as pastures.
The US Cordillera is the widest part of these mountains, so there is a greater variety of natural conditions. High, forested ridges with glaciers are close to vast desert plateaus. The climate is subtropical, and on the coast - Mediterranean, in the interior, where moisture from the ocean no longer gets, it is arid. On the slopes of the Front Range and the Sierra Nevada there are mountain pine forests, the Coast Ranges - which are lower - are covered with groves of relic sequoia and hard-leaved shrubs - chaparral. But the forests in the west are largely cut down or burned down in forest fires - also through the fault of man.
Where people have settled, large animals are either destroyed or are on the verge of destruction: for example, the bison is almost completely destroyed. The rich animal world has been preserved only in very large reserves such as Yellowstone and Yosemite National parks.
The bulk of the population is concentrated along the Pacific coast, where the major cities of Los Angeles and San Francisco are located.
The Mexican Cordillera is the Mexican Highlands and the California Peninsula. The climate is tropical, very dry, vegetation is poor, except for rainforest on the slopes of the mountains. Pronghorn antelope, coyote, monkeys, jaguar live here. Most of the population lives in and around Mexico City or in port cities.

general information

Mountain ranges: eastern belt (Brooks, Richardson, Mackenzie, Sawatch, San Juan, Forward, Uinta, Eastern Sierra Madre), inner belt (Kilbuck, Kuskokwim, Rey, Cassiar, Omineka, Columbian, Yukon Plateau, Stikine, Fraser, Snake, Great Basin, Colorado and Mexican Highlands), western (Alaska, Aleutian, Coastal, Sierra Nevada, Transverse Volcanic Sierra, Sierra Vizcaino, St. Elias Massif, Cascade and Chugach Mountains).

Plateaus, uplands and plateaus: Yukon, Fraser, Colombian, Colorado, Mexican.

Administrative affiliation: USA, Canada, Mexico.
Large cities: Mexico City - 8,851,080 people (2010), Los Angeles - 3,928,864 people. (2014), San Francisco - 852,469 people. (2014), Vancouver (Canada) - 2,313,328 people. (2011).
Languages: English, French, Indian dialects.

Ethnic composition: Whites, African Americans, Indigenous peoples.
Religions: Christianity (many branches and directions), Judaism, Islam.

Monetary units: Canadian dollar, US dollar, Mexican peso.

Large rivers (sources and upper reaches): Yukon, Peace, Athabasca, Mackenzie, Saskatchewan, Missouri, Columbia, Colorado, Rio Grande, Fraser.

Large lakes: Great Salt, Tahoe.

Numbers

Maximum Width: in Alaska - 1100-1200 km, in Canada - up to 800 km, on the territory of the United States itself - about 1600 km, in Mexico - up to 1000 km.

highest point: Mount Denali (Pacific belt, 6144 m).

Other peaks: Mount (5951 m), Volcano Orizaba (5700 m), Volcano Popocatepetl (5452 m), Mount Whitney (4418 m), Mount Elbert (4399 m), Volcano Rainier (4392 m), Volcano Nevado de Colima (4265 m), Mount Marques-Baker (4016 m), Mount Waddington (4042 m), Yliamna volcano (3075 m).

Glaciers: area - about 67 thousand km 2.

Climate and weather

January average temperature: in the north -30°С, in the south -17°С.
July average temperature: in the north +15°С, in the south up to +30°С.

Average annual rainfall: on the southern ridges of Alaska - 3000-4000 mm, on the coast of British Columbia - up to 2500 mm, on the internal plateau of the USA - up to 400-200 mm, in the Mojave Desert - 50 mm per year.

Relative humidity: from 70-80% in the north to 50-60% in the south.

Economy

Agriculture: in the north - reindeer breeding, in the temperate zone - cereals and cattle, in the south - citrus fruits.

Service sector: tourism, transport, trade.

Attractions

Curious facts

Any resident of North and South America knows where the Cordilleras are. These mountains stretch along the western side of the aforementioned continents: from Alaska (the northwestern part of North America) to the island of Tierra del Fuego, which is located not far from Antarctica. This is the longest Mountain chain in the world. Its length is 18,000 kilometers, and the width of the North American part reaches 1,600 kilometers (the maximum width of the South American part is 900 km). The mountain chain is usually divided into two halves: the Cordillera of North America and the Andes.

Cordillera - one of the highest mountains in the world

The Cordilleras are one of highest mountains in the world. Only the Himalayas, as well as several other mountain systems of the central part of Asia, surpass them in height. highest point- Mount Aconcagua, whose height is 6962 meters. Aconcagua is located in the South American part of the Cordillera, and highest peak North American part - Mount Denali (Mount McKinley), reaching 6190 m.

The mountain chain passes through all the climatic zones of America (with the exception of the Antarctic, subantarctic), due to which the climate, as well as the flora and fauna of these mountains, change greatly if you move from north to south (to a lesser extent from west to east). For example, the snow limit in the Cordillera of Alaska is 600 m, and in Bolivia it is 6500 m.

Minerals

Like any territory where mountains are located, the Cordilleras are the richest source of minerals, primarily a variety of ores:

• copper;
• zinc;
• gold;
• iron;
• platinum;
• tin.

The bowels of the mountains also contain many other metals, and oil, gas, coal, and even precious stones are mined there (the richest emerald deposits in Colombia and Brazil).

Significance

The influence of these mountains on the formation of culture, traditions, and lifestyle of the inhabitants of America is difficult to overestimate. On the territory where the Cordilleras are located, entire civilizations of the Indians were born, unique in their development and cultural heritage. And on a planetary scale, the Cordillera mountain range is a watershed between the Pacific basin and the Atlantic Ocean.

In the North American part of the mountains there is a range called the Rocky Mountains. This area is one of the most popular areas in the United States for tourism, recreation, mountaineering, skiing and so on. The most famous national parks are located here: Yellowstone (USA), Rocky Mountain (USA), Waterton Lakes (Canada) and others.

Despite the fact that few people live in large areas, the vulnerable nature of the region has been damaged, which is difficult to restore.

13 created in Alaska national parks, where typical natural complexes are protected, as well as local animal species - mountain sheep, caribou, black bear (baribal) and grizzly.

Cordillera of Canada and Northwestern United States

This part of the Cordillera system is characterized by a relatively low mountain height and relative narrowness. It includes the Canadian Coast Range, the inland Fraser Plateau, the Columbian Plateau, and the Rocky Mountains up to about 48°N. sh. The westernmost orotectonic zone passes into the islands here. It is only in the south that the region expands, as this zone "returns" to the mainland. Its southern border runs along the northern outskirts of the Great Basin and the Sierra Nevada mountains.

Young folded ridges of the coastal zone are fragmented and lowered. The intermountain valleys are flooded with the sea and are straits and narrow long bays, deeply protruding into the land. The coast ridge continues the Nevadian zone, but its height is less than that of Alaska (2000-3000 meters, in the south - up to 4000 meters). It is dissected and processed by glaciers. The coast here is fjord-like.

Some general lowering of the mountains of the region compared to other parts of the Cordillera is presumably explained by large area glaciation, both ancient and modern. It is possible that the earth's crust here, as it were, sags under the weight of ice. The inner plateaus are composed of lava covers reaching a thickness of up to 1200 meters. They are high (800-1500 meters), but narrow, expanding only to the south (Columbia Plateau - up to several hundred kilometers). Rivers, cutting through the plateau, form canyons. The Rocky Mountains consist of a series of longitudinal ridges up to 4000 meters high, separated by valleys and abruptly dropping to the east. A graben filled with glacial deposits stretches along the western slopes - the "Moat of the Rocky Mountains". It is believed that this is a continuation of the mid-ocean rift.

The amount of precipitation decreases from west to east (a common pattern for the Cordillera). The ocean coast receives 2000-3000 mm per year. Maximum - winter, snow cover in the mountains reaches an average thickness of up to 6-9 m. Summer is cool, cloudy. The climate is the same as on the coast of Alaska, only a little warmer.

Here, as well as on the coast of Alaska, "rain" coniferous forests of Sitka spruce, Douglas, western hemlock, etc. grow with dense undergrowth, epiphytic mosses, and ferns.

On the inner plateaus, features of continentality appear: there is little precipitation (300-400 mm), temperature amplitudes increase. In the north there are areas of taiga on podzolic soils, which are replaced by forest-steppe and steppe to the south. Wormwoods appear in the extreme south. The slopes of the Rocky Mountains are covered with pine forests and shrubs, while the valleys are treeless.

In the Cordillera of Canada a large number of mountain glaciers of various types.

The region is rich in minerals, both ore (copper, iron, lead, zinc, silver, gold) and non-metallic, such as coal. Forest resources and the hydro potential of rivers are used. Tourism is developed, especially in the mountains of British Columbia. A number of national parks have been created for nature protection - Jasper, Banff, Glacier, etc.

Cordillera of the Southwestern United States

The physiographic country is located approximately between 48 ° and 32 ° N. sh. in the widest and most diverse part of the Cordillera mountain system. The region experienced a general uplift in the Paleogene-Neogene, which was accompanied by faults, denudation, and large erosional dissection.

Here, the manifestations of faults are most clearly visible at the junction of the continental (North American) and oceanic (Pacific) crust. Quite clearly visible are the zones of deep subsidence of the oceanic crust under the continental crust in the California region, where there is a huge gap in the coastal areas. The San Andreas Fault extends in a northwesterly direction for almost 900 km. It has existed since the pre-Mello time, and is still very active today.

Three structural and morphological zones are clearly traced: axial, the most ancient - Nevadian, in the east - Laramian, in the west - young Cenozoic Coast Ranges, the development of which continues to the present.

Modern climatic conditions are characterized by high contrast, which is associated with the position in two climatic zones(temperate and subtropical), significant amplitudes of heights, the presence of mountain barriers in the path of sea air masses.

Areas with annual precipitation up to 100 mm and maximum temperatures up to +57 ° C (Death Valley) are adjacent to mountains where annual precipitation is up to 2000 mm and negative temperatures prevail even in summer (upper parts of the Sierra Nevada). In the west it has a Mediterranean type climate. In other parts of the region, climatic conditions features of continentality appear.

Different parts of the region differ significantly in all components of nature.

The eastern (Laramian) structures of the Rocky Mountains are often referred to as the continental divide, with elevations of 1,800 m and above.

The ridges are anticlinal folds that have Precambrian cores. Some of them are elongated in the general direction of the entire mountain system from northwest to southeast (the Front Range, Sangre de Cristo, etc.), but there are ranges of a different orientation, sometimes even sublatitudinal. Between them formed vast plateau-like areas connecting the Great Plains with the Great Basin - the so-called "parks". They are composed of sedimentary strata of Paleozoic-Mesozoic age. The summit areas were covered by the Wisconsin glaciation, preserved troughs and kars. Spruce-fir and pine forests are widespread on the slopes of the mountains, the bottoms of the "parks" are usually treeless. In the south and along the slopes of the mountains, steppes and semi-deserts rise.

In the northeast is the Yellowstone Plateau (“yellowstone” in English means “yellow stone”) with a Paleogene cover and young lava covers, having a thickness of more than 1000 meters.

It is known as one of the largest areas of the Earth with geysers and thermal springs. Under powerful lava covers (300-600 meters) forests of ancient sequoias are buried. Their petrified trunks are often found (there is a section with 12 layers of petrified forest covered with volcanic ash). In 1872, the Yellowstone National Park was founded here (an area of ​​about 900 thousand hectares, located at an altitude of 2100 m to 3400 m). There are 200 water thermal and mud springs, about 300 geysers on the territory of the park. The greatest geyser Exilor with a griffon diameter of 8-10 meters "works" here, which throws water up to 100 meters up. The mineral sediment forms geyserite of various shades - blue, purple, pink, etc. The wildlife of the park is rich - bison (their number has increased 20 times since the beginning of the century and amounts to several hundred heads), a variety of brown bear - grizzly, coyote, fox, skunk, badger, puma and 150 species of permanent birds. Access to the park is regulated. The park is divided into zones, each of which solves certain problems: there is a zone of strict protection, where no human influence is allowed, a zone of “managed” protection (to preserve natural landscapes), a zone organized tourism and a tourist-administrative zone (camping sites, parking lots, cafes, office buildings).

In the inner part of the physiographic country, west of the Rocky Mountains, there is the largest inland highland - the Great Basin and the Colorado Plateau.

The Great Basin has undergone a complex history of formation: Paleozoic and Mesozoic folding, Mesozoic sedimentation, and intense deformation of structures.

The modern relief was formed in the Cenozoic under the influence of submeridional faults along the rift between the Rocky Mountains and mountain range Sierra Nevada. Clastic material filled intermountain depressions. Active volcanism appeared in the northwest. At present, the rejuvenated topography with numerous internal drainless depressions has a large scatter. absolute heights- from 1500-2000 meters to -85 meters (Death Valley). This is the result of powerful vertical movements.

Due to the barrier role of the Cascade Mountains and the Sierra Nevada, which prevent the transfer of Pacific air masses, a climate with well-defined features of continentality has developed.

The annual amount of precipitation here does not exceed 90-100 mm. The result of the dry climate is the weak development of the river network, which has no flow into the ocean. There is no removal of destruction products outside the basin, so the clastic material buries and levels the mountainous terrain.

Within the highlands, there are a hundred relict lakes - the Great Salt Lake (the remnant of Bonneville Lake, most of which was drained by the Snake River).

The soil and vegetation cover and fauna are typical for deserts and semi-deserts of the temperate and subtropical zones. The Americas have a different appearance than the deserts of Eurasia.

Along with saline and rocky deserts, there are areas with a pronounced seasonality, when ephemera bloom brightly in spring. In the southern part of the basin, a “woodland” of cacti (up to 10 meters high) and yucca has formed. Pine and juniper with steppe grasses grow on the slopes of the ridges. Picturesque Sonoran Desert in Arizona. The hilly plain is composed of sedimentary rocks and has insular volcanic mountains. The desert is inhabited by many species of cactus, including the giant tree squaw. Volcanic mountains overgrown with this plant seem from afar to be covered with a sparse forest, devoid of small branches and leaves. The age of cacti is tens and hundreds of years, height 10-12 meters, trunk thickness up to 70 cm, coyotes and many poisonous snakes live under them. In addition to cacti, other xerophytic plants grow in Sonora, which can tolerate not only drought, but also extremely high air and soil temperatures. The fauna of the desert is diverse and interesting.

The Colorado Plateau is an area of ​​horizontal occurrence of Phanerozoic rocks of different lithological composition. A highly elevated structural plain (more than 3,500 meters in places) is framed by cuestas.

The deeply incised river network has created steep-sided canyons that expose all the different colored rocks that make up the plateau. On the outskirts of the plateau, volcanic rocks are widely represented in the form of intrusions and laccoliths. The main watercourse - r. Colorado, which cut through the plateau, creating the Grand Canyon. The main canyon has a winding shape, its depth is 1800 m, the maximum width is up to 25 km, and the length is more than 300 km.

To the west of the internal plateaus are Nevadian structures - the Sierra Nevada mountains. This is a large block structure (horst boulder with comb-like peaks), the blocks are inclined to the west, there are batholiths at the base. The Cascade Mountains are a prime example of a volcanic range with a active volcanoes. The folded structures within them are covered by Cenozoic lavas, and high (some higher than 4000 m) volcanic cones are planted on them. Among them there are also very active: in the 80s. 20th century Mount St. Helens erupted two years in a row, there were many deaths. There are also extinct, but showing post-volcanic activity.

The vegetation of the mountains is typically American.

Here in the valley Merset (Yosemite Valley) preserved forest (park) of the giant sequoiadendron. Behind big sizes(the height of many trees reaches 80-100 meters) and for bending, like mammoth tusks, their branches were called mammoth trees. In the lower tier of the mountains - chaparral (American variety of maquis).

Coastal ridges - low (up to 2400 meters) Pacific structures are separated from the Nevadian structures by the Willamette and California valleys. This is the result of subduction from latest education shifts and faults, such as, for example, San Andreas.

This fault is especially active. The blocks of the earth's crust move horizontally relative to each other at high speed. The process is accompanied by strong earthquakes. So, for example, in 1992, an earthquake occurred 150 km from Los Angeles in the Mojave Desert, during which more than 5,000 shocks of various strengths were recorded in 10 days. Large cities suffer from tremors - San Francisco was badly destroyed in 1906, in Los Angeles there were tremors of 7-8 points in 1971.

The climate is subtropical with humid warm winter(up to 10°C) and dry summers. On the coast, summers are cool (average July temperatures are about 15°C), due to the influence of air masses with a northern component and cold currents. When moving inland, summer becomes much warmer (20-22°C). The annual amount of precipitation is 500-600 mm with a winter maximum. The lower tier of mountains is occupied by an analogue of the Mediterranean maquis - chaparral (thickets of shrubby oak, deciduous and evergreen, 1.5-2 meters high, less often - 3 meters, on brown, above 600 meters - stony soils). In the south - thickets of acacia, cacti, yucca. The upper tiers are dominated by coniferous forests of Sitka spruce, Douglasia, pines, sequoias.

On the northern parts of the western slopes there are national parks, where evergreen sequoia forests (mahogany) are taken under protection. national park Redwood is located north of San Francisco, in the valley of the river. Redwood Creek. Sequoias are the tallest and oldest trees, along with mammoth trees from the same family. Sequoia grows up to 2000 years. The phytomass of the thousand-year-old sequoia is more than 4,000 thousand c/ha (1% is needles, the rest is the trunk and branches), the yield of commercial wood is 10 thousand m 3 /ha. Trees are not afraid of fires.

Of all the regions of North America, the Cordillera of the southwestern United States stands out for its variety of natural attractions that attract tourists from all over the world.

In addition to recreational, this region has good agro-climatic and land resources. In the Great California Valley, the natural vegetation of dry wormwood steppes and semi-deserts has been completely replaced by cultivated vegetation. On lands irrigated by the waters of rivers flowing down from the mountains, a variety of subtropical crops are grown. On the Pacific coast, giant urban agglomerations have formed, connected by high-speed highways. From Richmond, Oakland, San Francisco to Los Angeles, including the famous Hollywood, continuous urban development stretches.

The most acute problem is pollution: all harmful emissions remain near the surface of the earth, since a significant part of the year is dominated by the anticyclonic regime and descending air currents. Frequent fogs.