Coal and Its Classification

ВАРИАНТ 1

Igneous Rocks.

Igneous rocks have crystallized from solidified magma.

Igneous rocks can be classified in a number of ways and one of (hem is based on mode of occurrence. They occur either as intrusive (below the surface) bodies or as extrusive masses solidified at the Earth's surface. The terms "intrusive" and "extrusive" refer to the place where rocks solidified.

The grain size of igneous rocks depends on their occurrence. The intrusive rocks generally cool more slowly than the extrusive rocks and crystallize to a larger grain size. The coarser-grained intrusive rocks with grain size of more than 0.5 mm called plutonic or abyssal are referred to as intrusive igneous rocks because they are intruded into older pre-existing rocks. Extrusive or volcanic rocks have even finer grains, less than 0.05 mm and are glassy.

Exposed igneous rocks are most numerous in mountain zones for two reasons. First, the mountain belts have been zones of major deformation. Second, uplifts in mountain belts have permitted plutonic masses to be formed.

The largest bodies of igneous rocks are called batholiths. Batholiths cooled very slowly. This slow cooling permitted large mineral grains to form. It is not surprising that batholiths are composed mainly of granitic rocks with large crystals called plutons. As is known, granites and diorites belong to the group of intrusive or plutonic rocks formed by solidification of igneous mass under the Earth's crust. Granites sometimes form smaller masses called stocks, when the occurrence has an irregular shape but smaller dimensions than the batholiths.

Laccoliths and sills, which are very similar, are intruded between sedimentary rocks. Sills are thin and they may be horizontal, inclined or vertical. Laccoliths are thicker bodies and in some cases they form mountains.

Dykes are also intrusive bodies. They range in thickness from a few inches to several thousand feet. Dykes are generally much longer than they are wide. Most dykes occupy cracks and have straight parallel walls. These bodies cool much more rapidly and are commonly fine-grained. For example, granite may occur in dykes that cut older rocks.

Pegmatites (quartz, orthoclase and mica) also belong to the group of plutonic or intrusive rocks. They occur in numerous veins which usually cut through other plutonites, most often granite, or adjacent rocks.

Extrusive igneous rocks have been formed from lava flows which come from fissures to the surface and form fields of volcanic rocks such as rhyolite, andesite, basalt, as well as volcanic ashes and dust, tuff, etc. As a rule, these rocks of volcanic origin cool rapidly and are fine-grained. It is interesting to note that basalt is the most abundant of all lavatypes. It is the principal rock type of the ocean floor.

Igneous rocks are rich in minerals that are important economically or have great scientific value. Igneous rocks and their veins are rich in iron, gold, zinc, nickel and other ferrous metals.

1). Укажите, какие предложения соответствуют содержанию текста. Подтвердите свои ответы фактами из текста.

1. Igneous rocks have been formed by sedimentation.

2. Intrusive rocks have been formed by the cooling of rocks of the Earth's crust.

3. Extrusive rocks have been formed the same way.

4. The grain size of igneous rocks depends on mode of occurrence.

5. Exposed igneous rocks are numerous in mountain zones.

6. Granites and diorites belong to the group of extrusive rocks.

7. As a rule, granite may occur in dykes.

8. Pegmatites do not belong to the group of plutonic or intrusive rocks.

2). Ответьте на вопросы:

1. Have igneous rocks crystallized from magma or have they been formed by sedimentation?

2. Which types of igneous rocks do you know?

3. What does the grain size of igneous rocks depend on?

4. Can you give an example of intrusive or plutonic rocks?

5. Are diorites intrusive or extrusive formations?

6. What do you know about batholiths?

7. Do pegmatites belong to the group of plutonic or volcanic rocks?

8. How do pegmatites occur?

9. What minerals are igneous rocks rich in?

3.       а) Найдите в правой колонке русские эквиваленты следующих слов в сочетаний слов:

1.       adjacent layers                         а) способ залегания

2.       abyssal rocks                                 б) крупнозернистый

3.       dimensions of crystals             в) зоны крупных нарушений

4.       valuable minerals                          г) абиссальные (глубинные) породы

5.       shape and size of grains            д) смежные пласты (слои)

6.       mode of occurrence                      e) размеры кристаллов

7.       coarse-grained                               ж) взбросы

8.       uplifts                                      з) форма и размер зерен

9.       zones of major deformation       и) ценные минералы

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

1.       затвердевшие массы                  a) irregular shape

2.       обломочные породы                  б) at a certain depth

3.       медленно остывать                     в) economically important

4.       мелкозернистый                                          г) solidified masses

5.       многочисленные трещины       д) scientific value

6.       неправильная форма            e) to cool slowly

7.       на определенной глубине         ж) existing types of rocks

8.       экономически важный            з) fine-grained

9.       научная ценность                       и) fragmentary rocks

10.     существующие типы пород     к) numerous cracks or fissures

ВАРИАНТ 2

Metamorphic Rocks

The problem discussed concerns metamorphic rocks which compose the third large family of rocks. "Metamorphic" means "changed from". 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 composition and structure and are transformed into metamorphic rocks. The process described is called metamorphism.

As is known, metamorphic rocks have been developed from earlier igneous and sedimentary rocks by the action of heat and pressure.

Gneisses, mica schists, phyllites, marbles, slate, quartz, etc. belong to the same group of rocks. Having the same mineral composition as granite, gneisses consist chiefly of quartz, orthoclase and mica. However unlike granite, they have a schistose structure. It means that their constituents are distributed in bands or layers and run parallel to each other in one direction. If disturbed the rock cleaves easily into separate plates.

The role of water in metamorphism is determined by at least four variable geologically related parameters: rock pressure, temperature, water pressure, and the amount of water present.

During a normal progressive metamorphism rock pressure and temperature are interdependent, and the amount of water and the pressure of water are related to 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 consist of flaky materials such as mica and chlorite. These minerals cause the rock to split into thin sheets, and rocks become foliated.

Slate, phyllite, schist and gneiss belong to the group of foliated metamorphic rocks. Marble and quartzite are non-foliated metamorphic 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 original structure is of great importance to geologists. It gives an opportunity of analysing the causes of its metamorphism.

Being often called crystalline schists, metamorphic rocks such as 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.

1). Укажите, какие предложения соответствуют содержанию текста. 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 metamorphic rocks.

3. As is known, unlike granite metamorphic rocks have a schistose 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 preexisting rocks and the mechanism of metamorphic deformation as well.

9. All metamorphic rocks are non-foliated.

2). Ответьте на 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?

3.       а) Найдите в правой колонке русские эквиваленты следующих слов и сочетаний слов:

1.       as a result of the chemical and physical changes

2.       constituents of rocks

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

а)       полоса (или прослоек) угля

б)       составляющие пород

в)       расщепляться на отдельные слои

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)       pre-existing rocks

г)        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

ВАРИАНТ 3

Fossil Fuels

The chief sources of energy available to man today are oil, natural gas, coal, water power and atomic energy. Coal, gas and oil represent energy that has been concentrated by the decay of organic materials (plants and animals) accumulated in the geologic past. These fuels-are often referred to as fossil fuels.

The word fossil (derived from the Latin fodere "to dig up") originally referred to anything that was dug from the ground, particularly a mineral. Today the term fossil generally means any direct evidence of past life, for example, the footprints of ancient animals. Fossils are usually found in sedimentary rocks, although sometimes they may be found in igneous and metamorphic rocks as well. They are most abundant in mudstone, shale and limestone, but fossils are also found in sandstone, dolomite and conglomerate.

Most fuels are carbon-containing substances that are burned in air. In burning fuels give off heat which is used for different purposes.

Fuels may be solid, liquid and gaseous. Solid fuels may be divided into two main groups, natural and manufactured. The former category includes coal, wood, peat and other plant products. The latter category includes coke and charcoal obtained by heating coal in the absence of air.

Liquid fuels are derived almost from petroleum. In general, natural petroleum, or crude oil, as it is widely known, is the basis of practically all industrial fuels. Petroleum is a mixture of hundreds of different hydrocarbons — compounds composed of hydrogen and carbon — together with the small amount of other elements such as sulphur, oxygen and nitrogen. Petroleum is usually associated with water and natural gas. It is found in porous sedimentary rocks where the geological formation allowed the oil to collect from a wide area. Petroleum is one of the most efficient fuels and raw materials.

Of gaseous fuels the most important are those derived from natural gas, chiefly methane or petroleum. Using gaseous fuels makes it possible to obtain high thermal efficiency, ease of distribution and control. Gas is the most economical and convenient type of fuels. Today gas is widely utilized in the home and as a raw material for producing synthetics.

Scientists consider that a most promising source of natural resources may be the floor of the sea, a subject which now has become an important field of research.

Generally speaking, all types of fossil fuels described in the text are of great economic importance as they represent the sources of energy the man uses today.

1. Укажете, какие предложения соответствуют содержанию текста. Подтвердите свои ответы фактами из текста.

1.       Coal, water power and atomic energy are the only sources of energy available to man today.

2.       Coal, wood and peat represent natural group of solid fuels.

3.       As a rule fossil fuels are found in sedimentary rocks.

4.       Crude oil is widely used for producing solid fuels.

5.       Petroleum can be found in porous sedimentary rocks.

6.       Gas is used to produce synthetic materials.

7.       Not all types of fossil fuels burn.

2. Ответьте на следующие вопросы:

1.       What fuels are often referred to as fossil fuels?

2.       What does the word fossil mean?

3.       What rocks are most abundant hi fossil fuels?

4.       What types of fossil fuels do you know?

5.       Is coke a natural or manufactured solid fuel? And what can you say about coal and peat?

6.       How are coke and charcoal produced?

7.       What rocks is petroleum usually associated with?

8.       What are the advantages of gaseous fuels?

3. а) Найдите в правоq колонке русские эквиваленты следующих слов сочетаний слов.

1.       fossil fuel                                   а) дерево и торф

2.       raw material                              б) небольшое количество аргиллита

3.       crude oil                                                     в) органическое топливо

4.       the chief sources of energy          г) сланец и известняк

5.       to refer to                                   д) сырье

6.       any direct or indirect evidence of the deposit         e) материалы, содержащие углерод

7.       shale and limestone                 ж) главные источники энергии

8.       carbon-containing materials       з) любые прямые или косвенные признаки месторождения

9.       wood and peat                          и) сырая (неочищенная) нефть

10.     the small amount of mudstone  к) относиться к (чему-л.); ссылаться на (что-л.)

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

1.       древесный уголь и кокс            a) to collect data

2.       жидкое топливо                           б) charcoal and coke

3.       накапливать                            в) to be composed of limestones

4.       собирать данные                    г) liquid fuel

5.       происходить от                           д) to accumulate

6.       получать хорошие результаты е) to derive from

7.       богатый горючими сланцами  ж) to obtain good results

8.       состоять из известняков            з) abundant in oil shales

ВАРИАНТ 4

Coal and Its Classification

Coal is the product of vegetable matter that has been formed by the action of decay, weathering, the effects of pressure, temperature and time millions of years ago.

Although coal is not a true mineral, its formation processes are similar to those of sedimentary rocks.

Structurally coal beds are geological strata characterized by the same irregularities in thickness, uniformity and continuity as other strata of sedimentary origin. Coal beds may consist of essentially uniform continuous strata or like other sedimentary deposits may be made up of different bands or benches of varying thickness.

You can see a seam limited by two more or less parallel planes, a shape which is typical of sedimentary rocks. The benches may be separated by thin layers, of clay, shale, pyrite or other mineral matter, commonly called partings. Like other sedimentary rocks coal beds may be structurally disturbed by folding and faulting.

According tо the amount of carbon coals are classified into: brown coals, bituminous coals and anthracite. Brown coals are in their turn subdivided into lignite and common brown coal. Although carbon is the most important element in coal, as many as 72 elements have been found in some coal deposits, including lithium, chromium, cobalt, copper, nickel, tungsten and others.

Lignite is intermediate in properties between peat and bituminous coal, containing when dry about 60 to 75 per cent of carbon and a variable proportion of ash. Lignite is a low-rank brown-to-black coal containing 30 to 40 per cent of moisture. Developing heat it gives from 2,500 to 4,500 calories. It is easily inflammable but burns with a smoky flame. Lignite is liable to spontaneous combustion. It has been estimated that about 50 per cent of the world's total coal reserves are lignitic.

Brown coal is harder than lignite, containing from 60 to 65 per cent of carbon and developing greater heat than lignite (4,000-7,000 calories). It is very combustible and gives a brown powder. Bituminous coal is the most abundant variety, varying from medium to high rank. It is a soft, black, usually banded coal. It gives a black powder and contains 75 to 90 per cent of carbon. It weathers only slightly and may be kept in open piles with little danger of spontaneous combustion if properly stored. Medium-to-low volatile bituminous coals may be of coking quality. Coal is used intensively in blast furnaces for smelting iron ore. There are non-coking varieties of coal.

As for the thickness, the beds of this kind of coal are not very thick (1-1.5 meters). The great quantities of bituminous coal are found in the Russian Federation.

Anthracite or "hard" coal has a brilliant lustre containing more than 90 per cent of carbon and low percentage of volatile matter. It is used primarily as a domestic fuel, although it can sometimes be blended with bituminous grades of coal to produce a mixture with improved coking qualities. The largest beds of anthracite are found in Russia, the USA and Great Britain.

Coal is still of great importance for the development of modern industry. It may be used for domestic and industrial purposes. Being the main source of coke, coal is widely used in the iron and steel industry. Lignite, for example either in the raw state or in briquetted form, is a source of industrial carbon and industrial gases.

There is a strong tendency now for increased research into new technologies to utilize coal. No doubt, coal will be used as a raw material for the chemical industry and petrochemical processes. All these processes involve coal conversion which include gasification designed to produce synthetic gas from coal as the basis for hydrogen manufacture, liquefaction (разжижение) for making liquid fuel from coal and other processes.

1.Укажите, какие предложения соответствуют содержанию текста. Подтвердите свои ответы фактами из текста.

1. Anthracite coals may be divided into lignite and common brown coal.

2. Coals are ranked according to the percentage of carbon they contain.

3. Peat, with the least amount of carbon is the lowest rank, then comes lignite or brown coal.

4. Brown coal is hard and it is not liable to spontaneous combustion.

5. Bituminous coal weathers rapidly and one cannot keep it in open piles.

6. Being intensively used in the iron and steel industry bituminous coal varies from medium to high rank.

7. Anthracite or hard coal, the highest in percentage of carbon, can be blended with bituminous grades of coal.

2.Ответьте на следующие вопросы:

1. What is the classification of coal based on?

2. Is carbon the only element in coal? (Prove it.)

3. Is lignite intermediate in properties between peat and bituminous coal?

4. What heat value does lignite develop when burnt?

5. What coals are liable to spontaneous combustion?

6. What is the difference between lignite and brown coal?

7. Is bituminous coal high- or low-volatile?

8. Does anthracite contain 90 per cent of carbon?

9. Where are the largest deposits of anthracite found? And what can you say about bituminous coal?

10. What do you know about the utilization of coal?

3. а) Найдите в правой колонке русские эквиваленты следующих слов и сочетаний слов:

1.       spontaneous combustion а) легковоспламеняющийся газ

2.       moisture and ash content б) высокосортный уголь

3.       the most abundant variety                     в) плавить железную руду

4.       in its turn                     г) самовозгорание

5.       the amount of volatile matter    д) содержание влаги и золы

6.       easily inflammable gas e) дымное пламя

7.       brilliant lustre                  ж) наиболее широко распространенные угли

8.       to smelt iron ore            з) яркий блеск

9.       high-rank coal            и) в свою очередь

10.     a smoky flame            к) количество летучих веществ

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

1.       тип угля                                    a) heat value

2.       некоксующийся уголь            б) amount of carbon

3.       доменная печь                              в) coal rank

4.       содержание углерода                г) to store coal

5.       смешиваться с другими углями д) to weather rapidly

6.       улучшенного качества            е) non-coking coal

7.       складировать уголь               ж) blast furnace

8.       теплотворная способность      з) of improved quality

9.       быстро выветриваться и) to blend with other coals

ВАРИАНТ 5

aerial- а воздушный; надземный

certain- а определенный; некоторый; certainlyadv конечно

cost- (cost) v стоить; п цена; стоимость

crop- v (out) обнажать(ся), выходить на поверхность (о пласте, породе); syn expose;засевать, собирать урожай

dredging- n выемка грунта; драгирование

drill- v бурить, сверлить; n бурение, сверление; бурильный молоток; drilling -n бурение, сверление; core-drillingколонковое (керновое) бурение

drive (drore, driven) - v проходить (горизонтальную выработку); приводить в движение; управлять (машиной); п горизонтальная выработка; привод; передача

evidence – n основание; признак(и); свидетельства

expect - v ожидать; рассчитывать; думать; предлагать

explore- v разведывать месторождение полезного ископаемого с попутной добычей; exploratory -а разведочный; exploration -n детальная разведка; разведочные горные работы по месторождению

galena- n галенит, свинцовый блеск

indicate- v указывать, показывать; служить признаком; означать

lead- n свинец

look for- v искать

open up - v вскрывать (месторождение); нарезать (новую лаву, забой); opening -п горная выработка; подготовительная выработка; вскрытие месторождения

panning- n промывка (золотоносного песка в лотке)

processing- n обработка; - industryобрабатывающая промышленность

prove - v разведывать (характер месторождения или залегания); доказывать; испытывать, пробовать; proved -а разведанный, достоверный; proving -n опробование, предварительная разведка

search- v исследовать; (for) искать (месторождение); п поиск; syn prospecting

sign- n знак, символ; признак, примета

store- v хранить, накапливать (о запасах)

work - v работать; вынимать, извлекать (уголь, руду); вырабатывать; workable -а подходящий для работы, пригодный для разработки, рабочий (о пласте); рентабельный; working -п разработка, горная выработка

country rockкоренная (основная) порода

distinctive propertiesотличительные свойства

malleable metalковкий металл

Prospecting

Mining activities include prospecting and exploration for a mineral deposit through finding, proving, developing, extracting and processing the ore. That is why it is possible to divide the mining activity into three major phases: 1) before mining which involves prospecting and exploration required to locate, characterize and prove a potential ore body; 2) mining which refers to actual coal or ore extraction. Extraction processes include underground or surface mining and dredging; 3) after mining which involves processing and preparing the raw ore for the end product.

As has already been said, before a mineral deposit can be worked, that is, before it can be extracted from the Earth for use by man, it must first be found. The search for economically useful mineral deposits is called prospecting. To establish the quality and quantity of a mineral deposit, the type of country rock, etc. means to prove it and this process is called proving. Prospecting and proving are only two different stages of mining geological exploration, the latter includes drilling and driving of openings.

Last century prospectors looked for visible evidence of mineralization on the surface of the Earth. To recognize valuable minerals it was necessary to know their various distinctive physical properties. For example, gold occurs in nature as a heavy malleable yellow metal. -Galena, the most important mineral containing lead, is dark grey, heavy and lustrous. The first ores of iron to be mined were deposits of magnetite, a black heavy mineral capable of attracting a piece of iron.

As the deposits of mineral that cropped out at the surface were mined, the search for additional supplies of minerals took place. The science of geology was used to explain the occurrence of ore deposits.

The aim of geological prospecting is to provide information on a preliminary estimation of the deposit and the costs of the geological investigations to be made. It also indicates whether it is available to continue the exploration or not.

Prospecting work includes three stages: 1) finding signs of the mineral; 2) finding the deposit; 3) exploring the deposit.

General indications of the possibility of exposing this or that mineral in a locality can be obtained by studying its general topographical relief, the type of ground and its general natural conditions. Thus, in mountainous regions where fissures were formed during the process of mountain formation, ore minerals could be expected in the fissure fillings. In hilly regions, sedimentary deposits would be expected.

Certain deposits are found only in a particular type of ground. Coal seams, for example, are found in sedimentary formations mainly consisting of sandstones and shales. Veins, on the other hand, are found in crystalline (igneous) rocks, and the type of country rock usually determines the type of minerals.

At present, prospecting methods to be used are as follows:

1.    Surface geological and mineralogical prospecting such as panning.

2.    Geophysical, geochemical, geobotanical prospecting.

3.    Aerial photography with geological interpretation of the data to be obtained is highly effective from aircraft or helicopter. Besides, successful development of space research has made it possible to explore the Earth's resources from space by satellites.

In modern prospecting the methods mentioned above are used together with the study of geological maps.