The sixth lesson. The identification of rocks
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The sixth lesson.
THE IDENTIFICATION OF ROCKS
In spite of the difficulty in defining rocks, most rocks are easily recognized when you see
them, and most are made of minerals or mineral-like substances.
They are usually solid, hard, and heavy, compared to the other materials you see and use
The study of rocks is petrology. It is a difficult science, for most rocks are harder to identify than
birds, flowers or trees.
But the study of rocks is important, for rocks and minerals yield the materials that make modern
civilization possible. The rock which forms soil is the basis for life on land.
life possible to exist.
The identification of rocks is easy when the rocks are made of minerals and when the minerals
are large enough to be identified. When the rock is fine-grained and when the minerals all look
alike, as they do in some of the dark rocks, it takes skill to identify them. The geologist will often cut
a piece of rock with a diamond saw and polish one surface until it is perfectly smooth. He then
cements the smooth surface to a glass slide, and polishes the rest of the rock until it is paper thin.
This thin layer of rock is examined under a microscope, using Polaroid light.
As the light passes through the minerals in the rock, it is altered, producing beautiful colors.
These colors depend on the kind of minerals and on the angle at which the crystals have been cut.
Such patterns aid much in the process of identification.
The identification of rocks involves much more properties*.
The texture, color, hardness and relative weight of the rock* can also be used as clues.
The geologist also looks for the geologic structures in which the rock occurs.
Certain rocks are found only in volcanoes, others in caves. Still others are more likely to be
found in valleys than on high ridges.
tog‘ jinslarini aniqlash ko‘p
xususiyatlarini qamrab oladi
tog‘ jinsinining nisbiy og‘irligi;
ishlab chiqarishda maxsulot
miqdori, daromad, hosil bermoq;
to depend on
aralashtirmoq, jalb qilmoq;
vodiy, o‘lka, voxa
Describe the process of rock identification using the following words:
to look alike, fine-grained, skill, to identify, odd, a piece of rock, diamond saw, to polish, surface,
until, smooth, to cement, glass slide, paper thin, to examine, under microscope, Polaroid light, to
depend (on), angle, pattern, texture, color, hardness, relative weight, alteration.
1. When is the identification of rocks easy?
2. What can be used as clues in identification of minerals?
3. Why is it so important to study rocks? 4. What is the study of rocks called?
5. What is petrology? 6. How do the geologists identify rocks? 7. How many rocks do you know?
8. What does the sea water make salty?
look for, to eliminate, change, help, man-
made, bed, strange
to search for, to alter, odd, layer, to remove, aid,
alive, smooth, wet, possible, fine-grained,
likely, thin, organic, pure, ancient
rough, course-grained, unlikely, thick, dead,
dry, dirty,impossible, inorganic, modern
to mix, to consider, to alter, to exist, to produce, to identify, to recognize
b) Form adverbs from the following words. Translate them:
odd, main, correct, frequent, easy, perfect, hard, near (lovely, friendly, manly, lonely, silly, elderly,
VI. Give the translation:
a) man-made, smooth, alive, common, relative, liquid, to polish, desert, pattern, mixture, cement,
shale, coal, aid, mud, deposit, to exist, to identify;
b) ice field, sea animal, ocean life, mineral like substance, diamond saw, paper thin, glass slide,
Extraction enterprises, the largest mining, slake slime factory;
VII. Pronounce the following words and translate:
occasionally [ə'keiʒənəli], feldspar [feld`spa:], potash [`pͻtæ∫], glaze [gleiz], pottery [`pͻtəri],gypsum
[`dʒipsəm],conglomerate [kən`glͻmərət], limestone [laim`stəun], sediment [`sedimənt], oxide [`ͻksaid],
siltstone [`silstəun],shale, [∫eil], dolomite [`dͻləmait], igneous [`ignəs], extent [iks`tent],yield [`ji:ld].
VIII. Give the English for:
Cho‘l -biyobon, kon, aralashma, suyuqlik, botqoqlik, sun’iy, tekis, ko‘mir, odatiy, nisbiy, qum
barhanlari, biroq, kon, mavjudlik, silliqlamoq, sun’iy, tuproqli slanes, odatiy, nisbiy, g`ayritabiy,
qamrab olmoq, biroq.
IX. Choose the appropriate word.
1. Sometimes it is easy to make plans but difficult (to find, to show, to carry out) them.
2. Steel is a (easy, safe, strong) metal.
3. Could you (throw, cause, point out) the most beautiful pictures of your collection?
4. A new (subject, invention, substance) is usually much worked at in the laboratories until its properties
are well studied.
X. Translate into Uzbek or Russian paying attention to the word by:
1. Many substances are prepared by chemical methods.
2. New experimental methods are employed by chemists.
3. Thanks to Lodygin we can work by the light of the electric lamp.
4. The mechanical energy of a waterfall can be transformed into electrical energy by means of a water
wheel and a dynamo. 5. What is the time by your watch? 6. Six by seven is forty-two.
7. My brother is a fitter by trade.
8. By the end of the next year they will have graduated from the Institute.
9. The combining weights of elements can be found experimentally by determining how
many grams of the element unite with 8 grams of oxygen.
XI. Complete the sentences with the correct form of do, be, or have.
Some of the answers are negative. Example Have you ever been to Japan?
1 I work in a large company, but I ____ like it very much.
2 ____ you been waiting long? 3 It’s very hot today, ____ it?
4 I don’t understand what they ____ saying. 5 The job ____ advertised in last night’s paper.
6 You don’t see your parents very often. When ____ they emigrate?
7 ‘Have you moved house yet?’ ‘No, we ____ .’
8 A new road ____ being built through the town centre at the moment.
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