Главная страница Случайная страница


АвтомобилиАстрономияБиологияГеографияДом и садДругие языкиДругоеИнформатикаИсторияКультураЛитератураЛогикаМатематикаМедицинаМеталлургияМеханикаОбразованиеОхрана трудаПедагогикаПолитикаПравоПсихологияРелигияРиторикаСоциологияСпортСтроительствоТехнологияТуризмФизикаФилософияФинансыХимияЧерчениеЭкологияЭкономикаЭлектроника

Geographical position and mineral resources


1. Geographical Position.

2. Climate, Vegetation and Wildlife.

3. Mineral Wealth.


1. The USA is the most powerful and the most advanced capitalist country. It leads the world in industrial and agricultural production. The total area of the USA is about 9.4 million square kilometers. The population of the country is over 253 (260) million people. The capital is Washington. The USA (excluding Alaska and Hawaii) is situated in the central part of the North America continent. It stretches from the Atlantic Ocean in the east to the Pacific Ocean in the west, from Canada in the north to Mexico, the Gulf of Mexico, and the Gulf of California in the south. The continental part of the USA consists of four physical geographical parts: two highland and two lowland regions. The highland regions are the Appalachian Mountains in the east, and the Cordillera and the Rocky Mountains in the west. The Appalachian Mountains are very old. The Rocky Mountains are considered to be young, high, rough and irregular in shape.

Between the Rocky Mountains and the Appalachian Mountains there are central lowlands, called the prairie, and the eastern lowlands, called the Mississippi valley.

The 5 Great Lakes, between the USA and Canada, include Lake Superior, Lake Michigan, Lake Huron, Lake Erie and Lake Ontario. They are all joined together by short rivers or canals, and St. Lawrence River joins them to the Atlantic Ocean. In the west of the USA there is another lake called the Great Salt Lake.

The main rivers of the USA are the Mississippi, flowing south to the Gulf of Mexico; the Missouri, flowing into the Mississippi; the Rio Grande, flowing along the boundary between Texas and Mexico into the Gulf of Mexico; the Yukon, flowing north-west and south-west from Canada through Alaska to the Bering Sea; the Colorado, flowing into the Gulf of California; the Columbia, flowing into the Pacific Ocean, and the St. Lawrence River and the Hudson River, flowing into the Atlantic Ocean.

A RIVER THAT FLOWS BACKWARD: Years ago the Chicago River flowed north and emptied itself into Lake Michigan. But when Chicago began to expand and more drinking water was needed for its inhabitants, engineers got to work and deliberately altered the whole structure of the river, so that fresh water would then flow from the lake into the river. That result is that nowadays, instead of flowing north, the Chicago River flows south towards the Gulf of Mexico.

2) The USA is a very large country, so it has several different climate zones. The coldest regions are in the north and north-east, where much snow falls in winter. The south has a subtropical climate. Hot winds blowing from the Gulf of Mexico often bring typhoons. The climate along the Pacific coast is much warmer than that of the Atlantic coast. The region around the Great Lakes is known for its changeable weather. In general, the climate in North America is much colder than in Europe and the average annual temperature of New York, for example, is +11C.

In the East the principal trees are spruce, poplar, birch and fir. The Northern Appalachians and the upper Great Lakes region are dominated by mixed forests of birch, beech, maple, hemlock and pine. Much of southern Florida and the lower Mississippi River valley are covered by-marsh grasses. In the Western Mountains on the lower slopes are open woodlands. The warm-winter desert areas of Southwest support much cactus. The Pacific Northwest has dense coniferous forests with fir, hemlock, and spruce among the principal trees. Northwestern California has dense stands of giant redwoods (sequoias) along the coast.

Throughout Midwest and in much of Texas the native vegetation has been largely removed to make way for agriculture.

The animal population of the United States was both numerous and prolific in aboriginal times. Since the advent of the white man, with his firearms and with his need of land for agriculture, the animal population has been greatly reduced. Whole species have been exterminated, or preserved in other than the wild state.

The northeastern forests abounded in animals of all kinds and sizes. Deer, recoons skunks, grey and red squirrels, black bears, rabbits and hares, beavers, minks, and moles were common. Great flocks of birds were present, including migratory wild fowl. Reptiles included turtles, salamanders, and several species of snakes.

In the forests of the Southeast possums abounded and along the coasts were alligators and sea cows. Crocodiles were present in the extreme south of Florida. Great numbers of large birds, such as.the flamingo, the.whooping crane, were common in the swamps and marsnes.

The Interior Plains had vast herds of grazing animals, especially bisons (" buffaloes") and antelopes. The higher mountains of the West were the home of the mountain sheep, mountain goat, grizzly bear, marmot, and rock rabbit.

The deserts have a highly specialized world, equipped to avoid heat and reduce water losses to a minimum, like the sidewinder rattlesnake, which keeps much of its body off the ground to avoid contact with that searing surface.

2. The USA is noted for a great number and a great variety of mineral resources. Its territory possesses over 100 kinds of various minerals. In resources of coal, natural gas and lead the USA holds the 1st place. In resources of copper, zinc-the second. In resources of gold, silver, asbestos the 3d. At the same time the country lacks a sufficient supply of some of the minerals required for modern industries. These must be imported into the USA. They include tin, nickel, chrome, cobalt, and industrial diamonds. Modern industry demands more and more of the nation’s mineral wealth. The total resources of coal of the USA are equal to 1.5 trillion tones. The principal deposits of high-grade coals are concentrated in the eastern part of the country. The total reserves of oil are estimated to 5 thousand million tonnes. The chief oil-bearing area is in the southern part of the Interior Plains and the Gulf Coast Plain. The total resources of iron ore are 11 thousand million tonnes. The chief deposits of iron ore are concentrated in the region of Lake Superior. Large deposits of non-ferrous metals are to be found mostly on the territory to the west of the Mississippi River-zinc, copper, lead and others. Principal resources of such metals as gold, silver and rare elements are in the Cordilleras.

As a whole, the USA has considerable resources of mineral raw materials for the development of industry.


Поделиться с друзьями:

mylektsii.su - Мои Лекции - 2015-2024 год. (0.006 сек.)Все материалы представленные на сайте исключительно с целью ознакомления читателями и не преследуют коммерческих целей или нарушение авторских прав Пожаловаться на материал