MATERIAL OF THE LITHOSPHERE. ROCKS
THE ATMOSHERE
The Earth contains three essential parts, the lithosphere, the hydrosphere and the atmosphere which principally consists of oxygen and nitrogen and covers the Earth’s surface. People and animals must have oxygen or they cannot live, while plants, trees and grass cannot live without carbon dioxide. Besides oxygen, nitrogen and carbon dioxide there are small quantities* of other gases and moisture or water vapour. You must picture the Earth as a ball, surrounded by an envelope or a coat of air fifty miles thick where the upper layers with rarefied* air are pressing down on the lower layers with dense and heavy air. Wherever you are, the column of air is exerting a pressure equal to 15 pounds on every inch of your body, although you do not feel it. If you climb on the top of Mount Everest (30000 feet), you will find that the pressure is less than one-fifth what it is at sea-level and it is difficult to breathe at such a height.
*quantity - количество
*(to) rarefy - разрежать
RELIEF OF THE EARTH
The total area of the surface of the land and water of the Earth include the lithosphere (the solid outer part of the Earth) and the hydrosphere (the liquid part of the Earth) which form a geoid, slightly flattened near the poles and slightly bulged at the equator. The universal ocean which for convenience we divide into the Atlantic, the Pacific, the Indian and the Arctic oceans, covers one hundred forty one million square miles of the lithosphere. The continental platforms of North and South America, Africa, Eurasia, Australia and Antarctic represent the elevated portions of the lithosphere. However, the ocean overflows its basins and covers the lower margins of the area of the continental platforms which amounts to ten million square miles. The continents stand above the oceans. The continental shelves lie beneath the ocean and extend out from the continents varying distances. The slopes connecting the continental platforms and ocean basins, either steep or gradual, are called the continental slopes. Doubtless, the second order relief features are mountains, plateaus and plains. Mountains are conspicuous highlands with small summit areas that we classify according to their arrangement in systems, ranges, chains and groups. Plateaus may be seen on the flanks of or between mountain ranges. The surface irregularities * of plains are comparatively small. Since plains are lowlands, they occur on continental borders. They are coastal plains. If they occur in the interior of a continent, they are interior plains. The majority of the people live on plains.
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* irregularity – неровность, неправильность
CHANGES IN THE EARTH’S CRUST
We realize that changes are continually taking place on the surface of the Earth: a). the wearing away of the land or denudation; b). the removal of material or transportation; c). the laying down of this material in fresh places or deposition. The chief agents of denudation are the sun, wind, rain, frost, running water, moving ice and the sea. The heat of the sun is great during the day, and the rocks get hot, expand, burst so that cracks form. At night, the rocks get cold, contract, their cracks increase in size and the rocks gradually break up into pieces. The wind acts in two ways: either it blows loose particles of soil and dust away, or, armed with millions of sharp pieces of sand, blows against a cliff or mass of hard rock, polishes the surface and begins to eat away the hard rock. The rain, which loosens and carries away* the soil, has a very powerful action, especially in hot countries. Rain absorbs considerable proportion of carbon dioxide, which, in solution with water, dissolves certain hard rocks such as limestone or sinks into the ground, forming underground caves. When the rain falls, part of it fills up cracks in the rocks. When it gets gold, the water in the cracks freezes and expands, and one day when the ice melts, a piece of rock breaks off. A great part of rain water collects together, forming little streams which in their turn join up to form rivers. The streams cut little valleys; and when the rain helps to wash away the banks, the valleys become broader and broader. The force of water is sufficient to do a great deal of damage, especially after a storm when the stream is in flood, increased by the load of stones and sand. In cold countries, instead of rivers, we can find glaciers, gradually moving downwards and scooping out their valleys.
*carry away – нести, продолжать, уносить
MATERIAL OF THE LITHOSPHERE. ROCKS
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It is true that man has studied very intensively all available rocks and minerals through direct observation, but they constitute only a small fraction of all the materials of the Earth. Scientists have secured specimens from the slopes of Mount Everest, proving that the mountain was once beneath the sea. One can study the materials on the walls of the canyons or the deepest mines in the world. Several well borings for oil have reached great depths, and through the examination of the drill cuttings, one can determine the nature of the rocks at depth in the hole. However, all rock exposures so far available to man are small compared with the radius of the Earth. Igneous rocks are those resulting from the interior heat of the Earth, for example, those which reach the surface in volcanoes. During the long periods of geologic time, the forces of erosion change the eroded igneous rocks into a sedimentary rock. As a result of heat, pressure and movement, igneous and sedimentary rocks change their qualities*, forming metamorphic rocks which are generally crystalline.
quality* - качество
SOIL AND VEGETATION ZONES
The vegetation of Russia was greatly affected by the gradual cooling of the Earth which occurred after the Tertiary epoch. The luxuriant subtropical vegetation which prevailed in the country during the Tertiary epoch disappeared and was succeeded by a new type of vegetation, better adapted to the cold climate of the Ice Age. Russia can be divided into several latitudinal soil and vegetation zones or belts extending across the country. The tundra belt lies along the coast and on the islands of the Arctic Ocean; it is at widest in northern Siberia and reaches as far south as sixty degrees of Northern Latitude at the neck of the Kamchatka Peninsula. Its chief characteristics is the absence of forest vegetation. The extremely low temperatures hinder the development of physical and chemical decay of the scanty plant cover and produce only a thin top layer of humus above the permanently frozen subsoil. The short growing season, the low annual average temperatures, the low precipitation and the thin though extended snow cover make it difficult for plants to exist. Dwarf birches and willows hug the ground where warmer temperatures prevail. In the south the wooded tundra forms a transition to the true forest. The wooded tundra gradually becomes denser and is followed by the taiga or coniferous forest belt. This vast belt comprising* about one-third of the forest land of the world, extends through the northern part of European Russia across the Ural Mountains and over most of Siberia. In the European part of Russia pine and spruce are the common species. Toward the Urals they merge with Siberian larch, fir and stone pine. The most widespread species in Eastern Siberia is the larch. The subzone of mixed and deciduous forests extends in the form of a wedge from the western frontier of Russia to the Ural Mountains. In Siberia its extent is negligible. Side by side with coniferous types, the mixed forests include elm, oak, maple and ash. Large sections of the forest zone are covered by marshes and peat bogs. This is especially true of Western Siberia where considerable precipitation and poorly developed watershed area produce marshes extending over tens of thousands of square miles. The steppe zone extends in an uninterrupted belt from the western border of Russia to the Altai Mountains, where the soil – Russian chernozem – is rather clayey, arable and productive. Alpine vegetation occurs below the snow line throughout the mountain regions of Russia, where the location of the Alpine meadow belt varies from 1000 feet in the Northern Urals to 8000 feet in the Altai mountain system in the south.
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* to comprise - включать, заключать в себе
Christopher Columbus
Christopher Columbus was born in Genoa, Italy, in 1451. He was the oldest of five children in his family. He didn't get to go to school very much, but he learned to read and write Spanish during his travels. He also taught himself Latin because all the geography books were written in Latin.
Some people thought he was trying to prove the world was round, but this is not true. Most people already knew the earth was round. He wanted to find a short way to get to the Indies by ship. He was a Christian and wanted to tell the story of Christ to the people he would find in the far-away lands. He also wanted wealth for himself and for Spain, and he wanted to be famous.
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He tried for eight years to get King Ferdinand and Queen Isabella to supply him with ships and money. Finally they agreed, but he made more demands. He wanted to be made a knight, admiral of the Ocean Sea. He wanted to be the viceroy and governor general of all lands he would discover. Also he wanted one-tenth of everything he found of value in the new lands. He even boldly told them he wanted all of this in writing.
They finally agreed and he got three ships ready to sail; the Santa Maria and two smaller ships, the Pinta and the Nina. He took enough food for a year. In four months he was ready to sail. They left Spain on August 3, 1492. After many days, the sailors were ready to turn around and start back home. "Just three more days," he said. "Then if we don't see land, we'll turn around and go back home." Two days later they saw land; an island Columbus named San Salvador. He thought he had found the Indies and called the people he saw there "Indians". When they got to Cuba, he thought he was in China. The world was a lot larger than he thought. On Christmas Eve, the Santa Maria was wrecked near Haiti. Columbus built a fort and left 40 men to hunt for gold. Then he returned to Spain on the Nina. The Pinta also returned. The people of Spain welcomed him as a hero. He made three more voyages across the ocean. His 13-year-old son, Ferdinand went with him on the fourth voyage.
Columbus did not become rich as he had hoped. At the end of his life he only had a pension the king and queen had given him because he was the first to reach the New World. He spent the last few months of his life in bed because of the pain of arthritis.
Columbus not only discovered a New World, but he led the way for other explorers.
THE CLOUD-MOBILE
Above my face is a map.
Continents form and fade.
Blue continents, made
On a white sea, are erased,
And white countries traced
On a blue sea.
It is a map that moves,
Faster than real,
But so slow.
Only my watching proves
That island has being,
Or that bay.
It is a model of time.
Mountains are wearing away,
Coasts are cracking,
The ocean spills over,
Then new hills
Heap into view
With river-cuts of blue
Between them.
It is a map of change.
This is the way things are
With a stone or a star.
This is the way things go,
Hard or soft,
Swift or slow.
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