Прочитайте следующие слом и сочетания слов 1-2 раза про себя, затем вслух и постарайтесь запомнить их.

at leastпо крайней мере to give an opportunity(of) давать возможность (кому-л., чему-л.) In sucha way таким образом 21. а) Определите по словообразовательным элементам (суффиксам и префиксам), какой частью речи являются следующие слова. Переведите их: known — unknown; differ — different — difference; found — founder — foundation; mean — meaning; difficult — difficulty б) Переведите на русский язык прилагательные с суффиксом-able: changeable, understandable, valuable, variable, breakable •) Заполните пропуски прилагательными, образованными от вы­деленных глаголов или существительных: 1. Under the action of pressure and high temperature rocks change their composition and structure. One may say that the struc­ture and composition of rocks are ....

band[btend] л слой; полоса; про­слоек (породы); syn layer

cleave[kli:v] v расщепляться; трес-• каться, отделяться по кливажу; cleavagen кливаж

constituent[kan'stitjusnt] л состав­ная часть, компонент

define[di'fain] v определять, да­вать определение

[dis'tnbjurt] v (among) рас­пределять (между); раздавать s'ta:b] v нарушать; смещать

excess[ik'scs] л избыток, изли­шек; ant deficiency[di 'fi/(s)nsi]

flaky['fleiki] а слоистый; похожий на хлопья

fluid[ 'flu(:)id] л жидкость; жидкая или газообразная среда

foliate[Toulieit] v расщепляться на тонкие слои; foliatedа лис­товатый, тонкослоистый; syn flaky

marble[ 'ma:bl] л мрамор

mention['теп/(э)п] v упоминать, ссылаться; л упоминание

plate[pleit] n пластина; полоса (металла)

pressure['рге/э] л давление; rock pressure (underground pressure)горное давление, давление горных пород

relate[ri'leit] v относиться; иметь отношение; relatedа родствен­ный; relationл отношение; re­lationshipл родство; свойство; relativeа относительный; соот­ветственный

run [глп] (ran [ran], run)v бегать, двигаться; течь; работать (о машине); тянуться, прости­раться; управлять (машиной); вести (дело, предприятие)

schistose['Jistous] _a сланцеватый; слоистый

sheet|Ji:t] л полоса

slate[sleit] л сланец; syn shale

split[split] (split)v раскалываться, расщепляться, трескаться; syn cleave

trace[treis] л след; tracingл про­ слеживание

126______________________________________________ Unit 5

2. Everybody understands that metamorphic rocks have been
developed from earlier igneous and sedimentary rocks. It is quite ...
that these changes take place in texture, in mineral composition and
in structural features of rocks.

3. Soft rocks can break into pieces. They are ....

4. Rare metals are of great value. They are very ....

5. Rock pressure and temperature vary. The role of water in
metamorphism is determined by four ... parameters.

22. Переведите наречия, образованные от прилагательных с помощью
суффикса -1у.

chief главный — chiefly ..., general общий, основной — gener­ally ..., common общий — commonly ..., original первоначальный — originally ..., particular особенный — particularly ..., practical практический, фактический — practically ..., usual обычный — usually ..., wide широкий — widely ...

23. Прочитайте следующие сочетавм слов. Переведите их:

cleavage distribution the definition of rocks

geological disturbances schistose structure

schistose coal low-grade metals

medium-grade coals high-grade oil
the most common metamorphic exposed igneous rocks

rocks single oithoclase crystals

chemically active fluids scientific value

rock pressure water pressure

excess of water thin sheets

foliated and non-foliated the Earth's surface

metamorphic rocks separate plates

24. Определите значения выделенных слов по сходству их корней с
соответствующих слов в русском языке:

metamorphicrocks; some changes in texture;in mineral com­position and structure;the description of metamorphism;schistose structure; the roleof water; four variable geologicallyrelated pa­rameters;flaky materials; the mechanism of metamorphic deforma­tion; crystallineschists; the great dislocationsof the Earth's crust; during normal progressive metamorphism

25. Прочитайте текст Б и найдите в нем ответы на следующие вопросы:

1. What is metamorphism?

2. Why can metamorphic rocks cleave easily?

3. Why is the study of metamorphic rocks important?

Unit 5__________________________________________ 127

ТЕКСТ Б Metamorphic Rocks

The problem discussed concerns metamorphic rocks which compose the third large family of rocks. "Metamorphic" means "changed frop". It shows that the original rock has been changed from its primary form to a new one. Being Subjected to, pressure, heat and chemically active fluids beneath the Earth's surface, vari­ous rocks in the Earth's crust undergo changes in texture, in mineral corhpositioh and structure and are transformed into meta-morphic rocks. The process describeci is called metamorphism.

As is known, metamorphic rocks have been developed from ear­
lier igneous and sedimentary rocks by the action of heat and pressure.
^ Gneisses, mica schists, phyllites, marries, slate, quartz, etc.
belong to the ⁷sarhe group of rocks,having the same mineral com-
position as granite, gneisses consist chiefly of quartz, orthoclase
and mica^. However unlike granite, they have a schistose structure. It
means that their constituents are diatributed in bands or layers and
rar^ parallel to each other in one 'Direction. If disturbed the rock
Cleaves easily into separate plates.

The role of water in rnetamorphism is deterrnine^ by at least four variable 'geologically refuted parameters: rock pressure, tempera-

ture .water pressure, and the amount of water present.

^? During a normal progressive metamorphism rock pressure and temperature are iriterciependent, and the amount of water and the pressure of water are related the sediments and to the degree of metamorphism in' such a way that,generally. speaking, the low-grade metamorphic rocks are characterized by the excess of water. The medium-grade rocks defined by some deficiency of water and the high-grade metamorphic rocks are characterized by the absence of water.

Many of the metamorphic rocks -mentioned above consjst,of flaky materials such as mica and chlorite. These minerals cause the' rock to split into thin sheets, and rocks become foliated.сг-оисъи

Slate, phyllite, schist and gneiss belfcng to the group of foliated
metamorphic rocks. Marble and quartzite are non-foliated metamor­
phic rocks,

The structure of metamorphic rocks is of importance because it shows the nature of pre-existing rocks and the mechanism of metamorphic deformation. Every trace of^{c original} structure is of great importance to geologists. It gives an opportunity of analysing the causes of its metamorphism.

128______________________________________________ Unit 5

Being often called crystalline schists, metamorphic rocks such asi gneisses and mica have a schistose structure. Metamorphic rocks represent the oldest portion of the Earth's crust. They are mostly found in the regions of mountain belts where great dislocations on the Earth once took place.

УПРАЖНЕНИЯ

26. Укажите, какие предложен» соответствуют содержанию текста Б.
Подтвердите свои ответы фактами из текста.

1. Generally speaking, metamorphic rocks have been developed
from ores.

2. Marble, slate and phyllite belong to the group of metamor­
phic rocks.

3. As is known, unlike granite metamorphic rocks have a schis­
tose structure.

4. It is quite obvious that the role of water in metamorphism is
great.

5. As a rule, low-grade metamorphic rocks are characterized by
the absence of water.

6. Flaky materials cause the rock to split into thin sheets.

7. It should be noted that marble and quartzite are foliated
metamorphic rocks.

8. The structure of metamorphic rocks shows the nature of older pre­
existing rocks and the mechanism of metamorphic deformation as well.

9. All metamorphic rocks are non-foliated.

27. Ответьте на следующие вопросы:

1. Do you know how metamorphic rocks have been formed?

2. Which rocks belong to the group of metamorphic?

3. Does gneiss have the same structure as granite?

4. Is the role of water great in metamorphism?

5. What rocks do we call foliated? What can you say about non-
foliated metamorphic rocks?

6. How can geologists trace the original structure of metamorphic
rocks?

7. Why are metamorphic rocks often called crystalline schists?

28. i) Найдите в правой колонке русские эквиваленты следующих слов и
сочетаний слов:

1. as a result of the chemical а) полоса (или прослоек) угля

and physical changes б) составляющие пород

2. constituents of rocks в) расщепляться на отдельные слои

Unit 5

3. to be subjected to constant

development

4. to undergo changes

5. excess of water

6. low-grade ores

7. coal band

8. to cleave into separate layers

9. traces of original structure

10. generally speaking

г) вообще говоря

д) в результате химических и

физических изменений

е) избыток воды

ж) изменяться

з) находиться в постоянном

развитии

и) низкосортные руды к) следы первоначальной структуры

б) Найдите в правой колонке английские эквиваленты следующих слов и сочетаний слов:

1. иметь значение 2. упомянутые выше 3. сланцеватая структура 4. в отличие от гранита 5. недостаток воды 6. существовавшие ранее породы 7. слоистые породы 8. мрамор и сланец 9. гнейс

10. давать возможность 11. определять структуру

а) unlike granite

б) to be of importance

в)
r) mentioned above

д) schistose structure

е) to give an opportunity (of doing

smth)

ж) to define (determine) rock texture

з) deficiency of water
и) flaky rocks

к) marble and slate л) gneiss

29. Заполните пропуски в предложениях, используя следующие слова:
cleave cleaves cleavage

1. Metamorphic rocks which have a schistose structure can ....

2. As a result of splitting ... is formed.

3. Generally speaking, the constituents of gneisses are distributed
in bands or layers and the rock ... easily.