English for Geographers

English For Geographers_____________________________________________

The formula CaCO3 describes not only the composition of calcite but also that of aragonite, a less common mineral with a different crystal form, hardness, density, and so on; the chemical name calcium carbonate alone does not distinguish between calcite and aragonite.

Calcite often contains small quantities of MgCO3 and FeCO3, and its composition is not precisely represented by the formula CaCO3 because the iron and magnesium carbonates form an integral part of the calcite structure with Fe and Mg atoms replacing some of the Ca atoms in the crystal lattice.

Many other mineral formulas besides that of calcite apply to two or more distinct substances and most minerals show a similar slight variability in composition. Hence chemical names are seldom really applicable, and the student of minerals finds necessary a new nomenclature.

Luckily, for present purposes we need only a few additions to our vocabulary. More than 2,000 different minerals are known, but most of these are rare. Even among the commoner minerals, the greater number occur abundantly only in occasional veins, pockets, and layers. The number of minerals that are important constituents of ordinary rocks is surprisingly small, so small that acquaintance with less than a dozen is adequate for an introduction to geology.

Mineral Properties

Common minerals are not only limited in number but are also easily recognisable with some experience, often by appearance alone. To distinguish the rarer minerals microscopic examination and chemical tests may be necessary, but for the minerals that compose ordinary rocks such simple physical properties as density, colour, hardness (Table), and crystal form make identification relatively straightforward.

In describing the important rock-forming minerals, two properties need special attention: crystal form and cleavage. Most minerals are crystalline solids, which means that their tiny particles (atoms, ions, or atom groups) are arranged in lattice structures with definite geometric patterns. When a mineral grain develops in a position where its growth is not hindered by neighbouring crystals, as in an open cavity, its inner structure expresses itself by the formation of perfect crystals, with smooth faces meeting each other at sharp angles. Every mineral has crystals of a distinctive shape so that well-formed crystals make recognition of a mineral easy; unfortunately good crystals are rare, since mineral grains usually interfere with one another’s growth.

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Table 2

The hardness scale. Each mineral can scratch those lower on the scale and in turn can be scratched by those higher on the scale. A fingernail is about

2.5in hardness and a knife blade is about 5.5.

1.Talc (softest)

2.Gypsum

3.Calcite

4.Fluorite

5.Apatite

6.Orthoclase

7.Quartz

8.Topaz

9.Corundum

10.Diamond (hardest)

Even when well-developed crystals are not present, however, the characteristic lattice structure of a mineral may reveal itself in the property called cleavage. This is the tendency of a substance to split along certain planes, which are determined by the arrangement of particles in its lattice. When a mineral grain is struck with a hammer, its cleavage planes are revealed as the preferred directions of breaking; even without actual breaking, the existence of cleavage in a mineral is usually shown by flat, parallel faces and minute parallel cracks. The flat surfaces of mica flakes, for instance, and the ability of mica to peel off in thin sheets show that this mineral has almost perfect cleavage. Some minerals (for example, quartz) have practically no cleavage; when struck they shatter, like glass, along random curved surfaces. The ability to recognise different kinds and degrees of cleavage is an important aid in distinguishing minerals.

3.Answer the following questions:

1.What are rocks?

2.What do rocks consist of?

3.How can the separate minerals be discerned in rocks?

4.Why do certain substances occur as minerals and why do not others?

5.What does the study of minerals require?

6.Do most minerals show in composition?

7.What properties need special attention in describing the important rock-forming minerals?

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4.Put questions to the following statements:

1.Rocks are aggregates of substances called minerals, which are crystalline solids with fairly definite compositions and structures.

2.The number of minerals that are important constituents of ordinary rocks is surprisingly small.

3.Various metals are obtained from deposits of sulphide minerals, such as galena (lead sulphide) and sphalerite (zinc sulphide).

4.Every mineral has crystals of a distinctive shape so that well-formed crystals make recognition of a mineral easy.

5.Insert the missing letters and translate the following words: cr…stal…ine, sub…tan…e, a…quaint…nce, in…er…ere,

…ar…onates, reco…nitio…, …ro…erty, cl… …vage, ab…ndan…ly, q…a…tity, s…rfa…e, re…e…l, …avit…, la… …ice, …aralle…,

6.Read the text again carefully, looking up anything you do not understand. Then answer the following questions:

1.From the headings to the two main sections of the text, what do you expect the two sections will be about?

2.What does the table show?

3.What is a mineral?

4.What rock is made up of one mineral only?

5.Is chlorine a chemically inactive element?

6.What do sodium chloride, sodium carbonate and potassium have in common?

7.What are the commonest minerals?

8.Why do you need to learn a special list of names to study minerals?

9.How many minerals are known to exist?

10.To start studying geology, how many minerals do you need to know about?

11.What are crystal form and cleavage?

12.Does every mineral contain crystals of the same shape?

7.Look at the first two paragraphs and say which words are used to mean:

● different materials brought together into a mass ● most/ the greater part or number

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●distinguish

●can be dissolved in a liquid

●likely to move or change

8.Look at paragraph 3 and find three words that have the opposite meaning to rare.

9.Look at paragraphs 4, 5 and 6 and say which words in the text you could replace with:

●amounts

●exactly

●rarely

●changeability

●sufficient/ enough

10.Look at paragraph 7 and say which words in the paragraph mean:

●the way something looks

●make up

●uncomplicated/easy

11.Look at the rest of the text and explain what these words mean:

●crystalline solid

●grain

●cavity

●plane

●parallel

●flake

12.Complete the following paragraph, using each of these words once: substance, variety, various, abundant, combine, structure, free, compound

Next to oxygen, the most ……… element in the earth’s crust is silicon.

Silicon never occurs ……… in nature, but its ……… make up about 87 percent of the rocks and soil under our feet. Nearly all the earth’s silicon is either ……… with oxygen alone or with oxygen and one or more metals in the ……… silicate minerals. As a class, these ……… are crystalline solids with high melting points. Their differences in composition and ……… are reflected in a ……… of colours, hardnesses and crystal forms.

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13.Complete the following paragraph using appropriate forms of the words in brackets:

Clay is an (especial) ……… (interesting) ……… material because of its ability to absorb (large) ……… amounts of water. This ability can be traced to the layered structures of the clay minerals. In many of these minerals, each layer is (electrical) ……… polarised, with one side exhibiting a (slight) ……… (positive) ……… charge and the other a (slight) ………

(negative) ……… charge. (Adjacent) ……… layers are held together by the attractions of the (opposite) ……… charges that face each other; since the layers are only (weak) ……… polarised, the bonds between the layers are (feeble) ……… , and (dry) ……… clay crumbles (easy) ……… .

14.Unscramble the following words and translate them:

Agagretegs, cyrsltas, rgaitne, mlietsone, lcevagae, elatitc, psroerptie, cocuspiunos, sdeitny, ngari, nmiuet, crhaactristeic, vriaabiylit, palicabple, vcaiyt, reogcniiton, cmpoosiiton, htaster, smiccroopic, svien.

15. Match the word with its explanation:

_____________________________________________English For Geographers

Section 2

1.Think of as many words as possible related to the theme ”Global Environmental Problems”. What can each of us do to protect the planet’s ecosystems?

2.Read and translate the following text using a dictionary:

Most of the world’s resources “used up”

Humans have destroyed two-thirds of nature’s machinery that supports life.

The human race is living beyond its means. A report backed by 1,360 scientists from 95 countries – some of them world leaders in their fields – warned that almost two-thirds of the natural machinery that supports life on the Earth is being degraded by human pressure.

The study contains what its authors call “a stark warning” for the entire world. The wetlands, forests, savannahs, estuaries and other habitats that recycle air, water and nutrients for living creatures are being irretrievably damaged. In effect, one species is now a hazard to the other 10 million or so on the planet, and to itself.

“Human activity is putting such a strain on the natural functions of the Earth that the ability of the planet’s ecosystems to sustain future generations can no longer be taken for granted”, it says. The report, prepared in

Washington under the supervision of a board chaired by Robert Watson, chief scientist at the World Bank and a former scientific adviser to the White House, was launched at the Royal Society in London. It warns that:

Because of human demand for food, fresh water, timber, fibre and fuel, more land has been claimed for agriculture in the past 60 years than in the 18th and 19th centuries combined.

An estimated 24 % of the Earth’s land surface is now cultivated.

Water withdrawals from lakes and rivers has doubled in the past 40 years. Humans now use between 49 % and 50 % of all available freshwater running off the land.

At least a quarter of all fish stocks are over-harvested. In some areas the catch is now less than a hundredth of that before industrial fishing.

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Since 1980 about 35 % of mangroves have been lost, 20 % of the world’s coral reefs have been destroyed and another 20 % badly degraded.

Deforestation and other changes could increase the risks of malaria and cholera, and open the way for new and so far unknown disease to emerge.

In 1997 a team of biologists and economists tried to put a value on the

“business services” provided by nature, the free pollination of crops, the air conditioning provided by wild plants, the recycling of nutrients by the oceans. They came up with an estimate of $ 33 trillion, almost twice the global gross national product for that year.

Flow from rivers has been reduced dramatically. For parts of the year, the Yellow River in China, the Nile in Africa and the Colorado in North America dry up before they reach the ocean. An estimated 90 % of the total weight of the ocean’s large predators – tuna, swordfish and sharks – has disappeared in recent years. An estimated 12 % of bird species, 25 % of mammals and more than 30 % of all amphibians are threatened with extinction within the next century.

A growing proportion of the world lives in cities, exploiting advanced technology. But nature, the scientists warn, is not something to be enjoyed at the weekend. Conservation of natural spaces is not just a luxury.

“These are dangerous illusions that ignore the vast benefits of nature to the lives of 6 billion people on the planet. We may have distanced ourselves from nature, but we rely completely on the services it delivers”.

3.Answer the following questions:

1.Is the human race supported in abundance with all the natural resources important for life?

2.What situation can we observe in the different habitats?

3.In what state are the different species of the world?

4.Will the planet’s ecosystems be able to sustain future generations?

5.What do scientists say about the present-day situation?

6.What can we really do to conservate natural spaces and to economise the world’s natural resources?

4.Put questions to the following statements:

1.The wetlands, forests, savannahs, estuaries and other habitats that recycle air, water and nutrients for living creatures are being irretrievably damaged.

2.Human activity is putting a strain on the natural functions of the

Earth.

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3.The ability of the planet’s ecosystems to sustain future generations can no longer be taken for granted.

4.Because of human demand for food, fresh water, timber, fibre and fuel, more land has been claimed for agriculture in the past 60 years.

5.Water withdrawals from lakes and rivers has doubled in the past

40 years.

6.In some areas the catch of fish is now less than a hundredth of that before industrial fishing.

7.Deforestation and other changes could increase the risks of malaria and cholera, and open the way for new and so far unknown disease to emerge.

8.Flow from rivers has been reduced dramatically.

9.A growing proportion of the world’s population lives in cities, exploiting advanced technology.

10.We rely completely on the services the nature delivers.

5. Insert the missing letters and translate the following words: ma…hiner…, wet…a…ds, f…res…s, sava……ahs, estu…ri…s,

ha…it…ts, re…y…le, …utri…nts, l…ving cre…tu…es, s…ec…es, h…zar…, st…ain, …u…tain, tim…er, l……nch, …upper…ision, …ibre, fu…l, fi…h sto…ks, f…ture gene…at…ons, ma…grov…s, …efore…tation, po……ination, pre…ato…s, ext…nct…on, b…nefi…s, …onservatio…, wate…wi……drawals.

6. Match a word in A with a word in B and translate the word-combina- tions obtained:

English For Geographers_____________________________________________

7.Complete the following paragraph, using each of these words more than once:

environment, resources, predators, surroundings, biotic factors, physical factors

………is the ……… in which animals and plants live. The study of organisms in relation to their ……… is called ecology. Organisms are affected by many different ……… in their ……… , such as temperature, water, gases, light, pressure, and also ……… such as food ……… , competition with other species, ……… and disease.

8.Complete the following paragraph, using each of these words more than once:

pollution, contamination, energy, natural resources, sewage, environmental resource, environmental threat, industrial wastes, noise, hazard, thermal pollution, ecological imbalance, populations, light pollution, wastes

………is the ……… of one substance by another so that the former is unfit for an intended use; or, more broadly, the addition to any natural ………

on which life or the quality of life depends of any substance or form of

……… at a rate resulting in abnormal concentrations of what is then termed the ‘pollutant’.

Air, water and soil are the ……… chiefly affected. Some forms of

……… , such as urban ……… and garbage or inshore petroleum spillage, pose an immediate and obvious ……… ; other forms, such as those involving potentially toxic substances found in ……… and agricultural pesticides, present a more insidious ……… : they may enter biological food chains and, by affecting the metabolism of organisms, create an ……… . ……… of organisms thriving abnormally at the expense of other ……… may themselves be regarded as pollutants. Forms of energy ……… include:

……… , e.g., factory, airport and traffic noise; ……… , e.g., the excessive heating of lakes and rivers by industrial effluents; ……… , e.g., the glare of city lights when it interferes with astronomical observations, and radiation from radioactive ……… . The need to control environmental ……… in all its aspects is now widely recognised.

9.Unscramble the following words and translate them. Then arrange them in the alphabetic order:

meahinryc, gderaed, dralatmicaly, amaalri, mngaroevs, polionlatin, ltehcnoogy, irngoe, witshrawdal, netier, ilusslion, xepilot, iproorpton, enersationg, setiatme, iocnservoatn, avlableai, cyreclign, ohrdswfis, maalsmm, pamhibnsia, meerge, suisipervon, ckssto.

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10. Match the word with its explanation:

Section 1

1. Learn the following words and their translation. Check up yourself by back translation: