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Explore it. The USA

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2017
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Explore it. The USA
Н. А. Овсянникова

Д. С. Ведунова

Данная книга является продолжением серии Explore it. Третья часть рассказывает об истории, традициях, географии и культуре США.

Explore it. The USA

Д. С. Ведунова

Н. А. Овсянникова

© Д. С. Ведунова, 2017

© Н. А. Овсянникова, 2017

ISBN 978-5-4490-0740-7

Created with Ridero smart publishing system

Geographical position and peculiarities of the country

The United States of America, often briefly referred to as the United States of America, the United States, or simply America, is a state in North America. The area is 9.5 million km² (4

place in the world). The population is 325 million people (2016, estimate, 3rd place in the world). The United States has a federal form of organization, administratively divided into 50 states and the federal district of Colombia; in their subordination there is also a number of island territories (Puerto Rico, the Virgin Islands, Guam and others).

The capital is the city of Washington. The United States borders the north with Canada, in the south – with Mexico, also have a maritime border with Russia. They are washed by the Pacific Ocean from the west, the Atlantic Ocean – from the east and the Arctic Ocean – from the north.

The United States of America was formed in 1776 with the unification of thirteen British colonies that declared their independence. The War of Independence lasted until 1783 and ended in the victory of the colonists. In 1787, the US Constitution was adopted, and in 1791 – the Bill of Rights, which significantly limited the powers of the government towards citizens. In the 1860s, the contradictions between the slave-owning southern and industrial northern states led to the beginning of the four-year Civil War. The consequence of the victory of the northern states was the widespread prohibition of slavery, as well as the restoration of the country after the split that arose when the southern states merged into the Confederation and declared their independence.

Location:

The main US territory (called continental states) is located on the North American continent and extends from the Atlantic Ocean in the east to the Pacific Ocean in the west. In the south, the United States borders Mexico, in the north – with Canada. In addition, the US includes 2 more states. The extreme north-west of the American continent is Alaska, also bordering Canada. In the Pacific Ocean is the state of Hawaii. The border with Russia passes through the Bering Strait. The United States also owns a number of islands in the Caribbean (for example, Puerto Rico) and the Pacific (American Samoa, Midway, Guam and others).

Subordinated territories

Under a particular US administration, there are (but are not included in) a number of island territories with different status. The Constitution of the United States fully operates on the territory of the uninhabited atoll of Palmyra. The remaining territories have their own basic legislation. The largest of these territories is Puerto Rico.

Relief

In the mainland, west of the Atlantic lowlands are the Appalachian mountains, behind which are the Central Plains (200—500 m above sea level), the Great Plains (600—1500 m) plateau. Almost the whole west is occupied by the Cordillera mountain system.

Most of the territory of the United States belongs to the North American platform. In the east it is framed by the Paleozoic Appalachian folded system, in the west by the Mesozoic-Cenozoic folded Cordillera system, in the south by the young plateau on the coast of the Gulf of Mexico, which passes northeast into the Atlantic flank of the same age. The foundation of the North American platform is exposed in the US territory in several small areas: Adirondack of the Canadian Shield (Middle Riphean rocks) in the states of Minnesota, Wisconsin and Michigan (rocks: granite gneisses over 3.5 billion years old, Archaean formation of greenstone belts and granites, Lower Proterozoic shelf deposits, quartzites, overlapping rocks of the Archean, Upper Proterozoic continental red clastic sediments, basalts and gabbros), in the Eastern Scalists mountains, in the states of Montana, Wyoming, Colorado, New Mexico, Arizona (north – Archean education, and to the south of Wyoming – Lower Proterozoic). The rest of the area is represented by acidic ground volcanics and granites. The platform cover within the continental United States has a Paleozoic age – from the very tops of the Cambrian or more often Ordovician to the lower Permian in the Peredapalach trough. Deposits of the Lower and Middle Paleozoic are predominantly shelf carbonates with subordinate packets of quartz sandstones and black mudstones («shales»). In the Michigan (Silurian) and Willstonian (Devonian) basins there are known evaporites (salts) and in the first of them – reefogenic limestones. Depositions of the Middle-Upper Carboniferous (Pennsylvanian system of American geologists) represent a paralyzed, cyclically constructed coal-bearing formation. It forms the central part of the Peredapalachsky trough, the basins (syneclise) of Michigan and Illinois (the Inner East coal-and-coal basin), Forest City and Celain (Inner Western Coal Basin), the intermediate elevation – the anteclise of Cincinnati and Ozark, and Bend in the south – the east – are composed from the surface of the Lower Paleozoic, and the wings are Silurian and Devonian. In the deep East Texas syneclise in the southwestern corner of the platform is a complete section of Permian sediments. The rocks of the Triassic and Jurassic (coastal-marine and continental) are known only in the west of the Great Plains, as well as in the large Willston syneclise. More often there are carbonate-terrigenous deposits of chalk – in a wide band from the Canadian border to the Gulf of Mexico. The Cenozoic deposits are of low power, the continental ones are limited, closer to the Rocky Mountains, along the foot of which the deflections of the Powder River, Denver and Reton are located. The southwestern corner of the platform is separated from its main part by the complex Wichita avlacogen, which extends to the west, in the northern part of the Colorado plateau.

The Rocky Mountains

The Rocky Mountains are the main mountain range in the Cordillera system of North America, in the west of the USA and Canada, between 60 and 32° N. w.

Rocky Mountains stretch for 4830 kilometers from north to south from the northern point in the province of British Columbia (Canada) to the state of New Mexico in the southwest of the United States. The width of the mountains reaches 700 kilometers. The Rocky Mountains are a natural watershed between the basins of the Pacific and Atlantic Oceans. In the Rocky Mountains, the rivers of Missouri, Colorado, Rio Grande, Snake, Arkansas and many others originate. Rocky Mountains were formed from 80 to 55 million years ago in the era of Laramie’s orogeny. Since then, under the influence of water and glaciers in the mountain range spectacular valleys and peaks were formed. At the end of the last ice age, people began to colonize the Rocky Mountains. After several expeditions, such as the journey of Alexander McKenzie or the expedition of Lewis and Clark, the Rockies began to settle; minerals and furs gave rise to the initial economic development of the mountains, despite the fact that the Rocky Mountains remained a sparsely populated area. Currently, most of the territory of the Rocky Mountains is protected by national parks and forest lands. Rocky Mountains – a popular place for tourists, especially for hiking, mountaineering, fishing, hunting, skiing, snowboarding and others.

The name «Rocky Mountains» was given by the Canadian pioneer of French origin Pierre Gauthier Varenne de la Verandry after he crossed the river Pierre Jaune (today it is Yellowstone – the river of yellow stone) on January 1, 1743. Alexander Mackenzie crossed the mountains in 1793 and named them «Stony Mountains». In the second half of the XIX century, the mountains were returned to the previous name.

The Northern Rocky Mountains (north of 45° N) are mainly composed of granites up to 3954 m in height (Robson Mountain); The southern Rocky Mountains, or the Rocky Mountains of the United States, consist of short ridges composed of sandstones, shales, limestones, up to 4,401 m (Albert Mountain – the highest point of the Rocky Mountains). There are extensive deposits of molybdenum, copper, gold, silver, polymetals, oil, and coal. Volcanic phenomena are observed: geysers, thermal springs, and earthquakes.

In the Rockies is a typical mountain climate. The average annual temperature in the valleys is within 6° C. In July, the warmest month, the average temperature reaches 28° C. In January, the average temperature is about -14° C, and this is the coldest month of the year. The average annual precipitation is about 360 mm.

In the Rocky Mountains in the summer it is usually warm and dry, as rain clouds from the west linger on the mountain ridge on its western side. The average temperature in summer is 15° C, and the average amount of precipitation is about 150 mm. Winters are very long and cold, with an average temperature of -2° C, and an average thickness of snow cover of 29 cm. In the spring, the average temperature is 4° C, and the precipitation is 107 mm. In autumn, the average rainfall is 66 mm and the temperature is about 7° C.

Vegetation – mainly forests, mountain-taiga in the north and pine in the south. The height of the forest boundary is from 1500 m (in the north) to 3600 m (in the south), higher – alpine meadows and eternal snow.

In the forests grow spruce, pine and fir, on the lower tiers, they mix with birches and white maple. Most of the mountains of the Arctic latitudes are covered with dwarf birches. On taiga soil not only coniferous, but also deciduous trees grow: birch, poplar and aspen.

In the valleys there are steppes and semi-deserts.

High-altitude animals here are snow goats, thick-nosed, elks and foxes. In the areas below, there is a marmot, a hare-hare, a black-tailed meadow dog and a coyote.

Most of the birds living in the Rocky Mountains are flying. In the summer months they feed the chicks here. Constantly in the mountains there live a three-toed woodpecker, a white partridge, some species of finches and owls.

In the Rockies are national parks Jasper (Canada), Banff (Canada), Yoho (Canada), Kootenay (Canada), Waterton Lakes (Canada), Glacier (USA), Yellowstone (USA), Rocky Mountain (USA).

Great Plains.

Great Plains – a piedmont plateau in the US and Canada, east of the Rocky Mountains. The height is about 700—1800 m above sea level. The length is about 3600 km, the width is from 500 to 800 km.

On the Great Plains are the territories of the Canadian provinces of Alberta, Manitoba and Saskatchewan and the American states of New Mexico, Texas, Oklahoma, Colorado, Kansas, Nebraska, Wyoming, Montana, North Dakota and South Dakota.

Great plains from north to south are divided into such major zones as the Missouri Plateau, the central High Plains, the Llano Estacado Plateau and Edwards. In some areas erosion of rocks is observed (these are the so-called bad lands, «badlands»). In the south they pass to the Mexican Highlands.

The climate within the plains is continental. Vegetation is mostly steppe.

On the plateau territory, wheat production is developed (the Great Plains are often called the «World Bread-Bread»), pasture cattle breeding. The US began to develop this area after the Louisiana purchase (1803). As early as 1820, researchers recognized these lands as unsuitable for life.

The Great Lakes

The Great Lakes (Grands Lacs, sometimes also the Great Laurentian lakes) are a system of freshwater lakes in North America, in the United States and Canada (Lake Michigan is entirely in the USA, the rest of the lakes and the short rivers that connect them cross the border between the USA (⅔ the water area) and Canada (⅓ the water area of lakes)). Includes a number of large and medium-sized reservoirs, connected by rivers and straits. The five largest ones are the Great Lakes themselves: Upper, Huron, Michigan, Erie and Ontario, although they sometimes include the St. Claire Lake, they form the largest group of freshwater lakes on Earth (a total area of 244,106 km², a total of 22,671 km³)), containing 21% of the surface in the world of fresh water (and 84% of freshwater in North America). Several middle lakes are associated with them, the most important of which are: St. Marys, Manitou, Nipigon, Nipissing. Lakes belong to the basin of the Atlantic Ocean, drain on the St. Lawrence River.

The formation of lake basins is most affected by tectonic processes; Great lakes began to form at the end of the last glacial period, about 10,000 years ago, when the mass of the glacier crushed the earth’s crust, and after the glacier melt, a slow reverse process began, glacioisostasis, which is also very noticeable in the Gulf of Bothnia and Finland. The water mass of the lakes was formed during the melting of the glacier. The northern coast of the Great Lakes rises faster than the southern one, which leads to the effect of «transfusion» of water and the slow flooding of lands in the south. Earlier, the Great Lakes had an additional runoff through the current rivers Illinois and Ottawa, but due to all the same geological processes, they, even today, near the shores of the lakes, changed their course somewhat and radically changed the source. As a result, today the natural runoff exists only along the St. Lawrence River.

With the help of canals, a waterway has been formed for sea ships with a length of about 3,000 km. Great lakes are connected by canals with the Hudson River and the Mississippi River basin.

Great lakes are among the largest on Earth accumulations of fresh water. Only Baikal and the glaciers of Greenland and Antarctica can compete with them. They are interconnected by rivers and canals, and therefore water flows from one to the other. The upper lake is the largest freshwater lake in the world, and Ontario alone is larger than the largest lake in Europe, Ladoga. Their average depth, not being very large, exceeds the average depth of the Baltic and North Seas.

The length of the coastline (with islands) is about 18 thousand km. The total area is 244,106 km², the basin area is 768,000 km² (including the area of the lakes themselves), the total volume of 22,671 km³, the four lakes of depth exceed 200 m and only Erie Lake has the greatest depth of 64 m, and St. Clare only 8. The largest and deepest of the Great Lakes is Lake Superior, the smallest – Lake St. Clair.

Several hundred small rivers flow into the Great Lakes, the flow from the lakes occurs along the St. Lawrence River, flowing from Lake Ontario and flowing into the Atlantic Ocean; the average water discharge at its source is 6637 m³ / s.

Previously, sewage, paper and other factories were discharged into these lakes. At first, the Erie Lake was significantly polluted, it was silt, many kinds of commercial fish disappeared from it. The government allocated significant funds for cleaning the lakes. Now the lakes are relatively clean. Great lakes are very important objects of rest and navigation.

The climate of the Great Lakes is humid, temperate, similar to the climate of the Middle Baltic. The area of the Great Lakes is characterized by sharp changes in weather conditions. This is due to the proximity of such different regions as the cold Hudson Bay in the north and the very warm Mexican Gulf in the south. The most variable season is winter, it is snowy, active cyclones are observed. Cyclones are also associated with frequent intrusions of Arctic air at this time, leading to a sharp cooling, and sometimes in a matter of hours frozen important areas for navigation. In winter, ice first covers Lake Superior, then – Huron and Michigan, lastly – Erie. The lakes are not frozen completely, but navigation stops, becoming impossible from December to April. Spring lasts a long time, often freezing. The summer is cool, it is, like winter, changeable, with frequent rains and a strong wind. Autumn includes a period of up to two weeks, called «Indian summer» with clear and dry weather. Autumn is considered the best season in the Great Lakes region.
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