Textl the changing earth

The study of geology has firmly established the great fact that the face of the earth, and the life upon it, represent merely a single phase of a tremendously long history which has involved many profound and far-reaching changes. For untold millions of years rocks at and near the surface of the earth have been crumbling under the weather; streams have been sawing incessantly into the lands; the sea has been eating into continental masses; the winds have been sculpturing desert lands; and more locally and intermittently, glaciers have plowed through mountain valleys and even vast sheets of ice have spread over consid­erable portions of continents. The outer shell of the earth has shown marked instability throughout geologic time. Slow upward and down­ward movements of the lands relative to sea level have been very com­mon, in many cases amounting to thousands of feet. Various parts of the earth have been, and are being, affected by sudden movements along fractures in the outer crust. During the eons of geological time, vast quantities of molten materials have, at intervals, been forced not only into the earth's crust, but also often out upon the surface. Moun­tain ranges have been brought forth and cut down, and sometimes rejuvenated. Sea waters have spread over many parts of what are now continental areas. There have been repeated advances and retreats of the sea over many districts. Lakes have come and gone. Plants and animals have inhabited the earth for many millions of years. The length of time of known human history is very short as compared to that of known geologic time. The former is to be measured by thousands of years, and the latter by tens or possibly hundreds of millions of years.

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■ Give the English for:

глубокие и далеко идущие изменения; представлять лишь одну фазу в ...; демонстрировать заметное непостоянство на протяже­нии геологического времени; движение суши вверх и вниз отно­сительно уровня моря; во многих случаях; насчитывать до...; вне­запные движения; время от времени; повторяющиеся наступле­ния и отступления суши; населять территорию; формировать ре­льеф суши; обновлять

Ш Give the Russian for:

to saw into; to eat into; to plow through; to spread over; to force into; to force out; to bring forth; to cut down

Ш Focus on structures:

• The length of time of known history is very short as compared to that of known geologic time.

• The former is to be measured by thousands of years, the latter by hundreds of millions of years.

И Follow the usage of tenses in the text.

Explain and expand:

• The face of the earth represents merely a single phase of a tremendously long earth's history.

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Text 2 CRUMBLING ROCKS

Probably there is nothing in Nature more grand and imposing than a lofty mountain, its towering peak snowcapped and glistening like a diadem in the sunlight, its enormous bulk fashioned from massive, solid rock. By contrast, nothing else on earth seems to be more firm and stable... There are numerous sayings to the effect that something is "as old as the hills" or "as hard as a rock".

On the other hand, if one will pause to think a moment, it is self-evident that even the hardest rocks are subjected to breakdown and decay. There are various examples of this on every hand. Inscriptions on old tombstones are slowly obliterated after many decades; surfaces of old stone edifices creemble away; stone steps of public buildings are gradually hollowed out by the constant tread of leather soles. Along country roads where the highway has been cut through rock strata, the stone soon loses its appearance of freshness, pitted surfaces develop, and pieces of rock slough off to collect in heaps at the base. If changes such as these occur within a few years or decades, infinitely greater ones must take place over periods of thousands or millions of years.

In nature, rock-weathering and erosion more or less keep pace with each other, thereby insuring retention of the soil mantle in regions where it has been developed. Here, ground water and air, penetrating down­ward through the interspaces of the soil, slowly weather the bedrock beneath, breaking it into smaller particles, even though the rock is blan­keted by many feet of mantle. If the topsoil is not carried away too fast, this slow weathering of the rock beneath continues in pace with the normal erosion of the world, the soil mantle, as a unit, would re­main essentially static were it not for improper agricultural practices that permit erosion to operate faster than new soil can be formed by 138

weathering. If researchers in rock-weathering could discover practical means whereby natural weathering could be greatly speeded, some of our serious erosion problems might be solved.

The profound effects resulting from the combined action of weath­ering and erosion account for nearly all the geologic changes that oc­cur on the surface of the earth. The only exceptions are the processes of volcanism, faulting and regional uplift, wherein new lands may be built and old ones shifted in position...

To weathering and erosion, then, may be attributed nearly all those natural features of the earth considered beautiful in the eyes of man: the towering mountains, peaceful valleys, sweeping hills, broad plains and dashing waterfalls. There are few individuals who can look upon beautiful scenery without experiencing some inward feeling of emotion at the wonders displayed before them. Such vistas may at first appear mysterious and meaningless but, upon study and contemplation, may be read like the pages of a book. It is the mighty history of an ever changing earth wherein rock piled on rock is slowly crumbled away, only to be rebuilt from the products of its own destruction into new rocks of some succeeding age. The Words of the prophet, written several millennia ago, still ring with truth:

The everlasting mountains were scattered, the perpetual hills did bow: his ways are everlasting.

Ш Give the Russian for:

by contrast; on every hand; to hollow out; within a few years; to keep pace with; thereby; to go in pace with; to account for; to be attributed to; inward feeling of emotion; upon study; wherein; there­by; to ring with trust

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И Give the English for:

с одной стороны; с другой стороны; иметь место; проникать сквозь; способы; средства; ускорять; значительное воздей­ствие; последующие годы

И Focus on structures.

• ...its towering peaks snowcapped and glistening .., its enormous bulk fashioned from massive solid rock

• nothing on earth seemed to be more firm and stable

• ... it is evident that even the hardest rocks are subjected to breakdown and decay

• if the topsoil is not carried away too fast,... the soil mantle would remain essentially static were it not for importer agricultural practices

• if researchers could discover practical means..., some of the problems might be solved

Explain and expand.

• In nature, rock-weathering and erosion more or less keep pace with each other.

• The profound effect resulting from combined action of weather-1 ing and erosion account for nearly all geologic changes that occur on the surface of the earth.

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