Consolidated rock – solid rock that underlies soils; consists of mineral or rock particles of different sizes and shapes that have been welded into a mass by heat and pressure or by chemical reaction. This rock must contain interconnected pores or fractures to serve as an aquifer.

Discharge – the volume flux of water.

Drawdown – the vertical drop of the water level in a well caused by ground water pumping; also, the difference between the water level before pumping and the water level during pumping.

Ground water – water found in the saturated zone of the subsurface. Ground water aquifer – a water-bearing layer of rock or sediment capable of yielding usable quantities of water; composed of unconsolidated materials such as sands and gravel, or consolidated rock such as sandstone or fractured limestone.

Overwithdrawal – withdrawal of ground water from an aquifer at a rate that exceeds the recharge rate of that aquifer. Can lead to lowered water table, saltwater intrusion and sinkholes.

Permeability – the capacity of a porous rock, sediment, or soil to transmit ground water. It is a measure of the inter-connectedness of a material's pore spaces and the relative ease of fluid flow under unequal pressure.

Pores – the spaces between particles within geological material (rock or sediment) occupied by water or air.

Porosity – is defined as the ratio of the volume of voids to the volume of aquifer material. It refers to the degree to which the aquifer material possesses pores or cavities which contain air or water.

Recharge area or zone – Recharge is the process that allows water to replenish an aquifer. This process occurs naturally when rainfall filters down through the soil or rock into an aquifer. Artificial recharge is achieved through the pumping (called injection) of water into wells or by spreading water over the surface where it can seep into the ground. The land area where recharge occurs is called the recharge area or recharge zone.

Salt water intrusion – the process by which over-pumping from an aquifer creates a flow imbalance within an area, which results in salt water encroaching into and contaminating a freshwater supply.

Saturated zone – the subsurface zone in which all pores in the aquifer are filled with water.

Spring – a place where ground water naturally comes to the surface at the intersection of the water table and land surface.

Subsidence – the sinking or depression of the land surface as a result of too much ground water withdrawal (or overwithdrawal of any mined fluid such as petroleum).

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Surface water – water found on the land surface in streams, ponds, marshes, lakes or other water bodies.

Unconsolidated material – material derived from the disintegration and erosion of consolidated rocks on the land's surface, as well as sediments deposited by coastal and glacial processes. Unconsolidated materials include, in order of increasing grain size, clay, silt, sand, and gravel.

Underground water – all water beneath the land surface. It includes water in the saturated and unsaturated zones.

Unsaturated zone – the subsurface zone in which the geological material contains both water and air in pore spaces. The top of the unsaturated zone typically is at the land surface, otherwise known as the vadose zone.

Watershed – all the land area and water within the confines of a drainage divide in which all surface runoff will pass through an identifiable outlet, such as a stream or river.

Water table – the top of an unconfined aquifer below which the pore spaces are generally saturated; the level in the saturated zone at which the pressure is equal to the atmospheric pressure.

Water table well – a well in which the source of water is an unconfined water table aquifer.

19. Match the English term with the Russian one.

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20. Match the terms with the definitions.

21.  Listen to the text where a commentator is talking about a hydrologist job. You will hear it twice. Answer the questions by saying whether the following statements are True (T) or False (F).

Mark it on the answer sheet. You have 30 seconds to read the questions.

1Hydrologists use various techniques and sophisticated equipment to monitor changes in water cycles.

2The work of hydrologists is not so significant in flood control.

3One of the crucial area in the work of hydrologists is environmental preservation.

4Experienced hydrologists spend little time in the lab.

5Certification in hydrology is recommended for most advanced employments.

22.  Listen to the text once again. For questions 1–10 complete the gaps.

You can use no more than 3 words. Before listening, look at the sentences and try to work out what kind of information you will need to listen for to fill each gap.

and equipment to monitor changes in water cycles.

The work of hydrologists is especially important in

5

They study

6

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Environmental

7

is another crucial area.

8 tend to spend much of their time in the lab.

Here they conduct tests,

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23. Look at the diagrams below and describe them. Use the following words and word combinations.

1.ground water, conical-shaped depression, pumping well, vicinity, deviate from.

2.beneath the land surface, saturated zone, unsaturated zone, filled with.

3.source of water, water table, unconfined aquifer, water level, some height above, the level at which.

Fig. 1

Fig. 2

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Fig.3

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UNIT 3

THE CIRCULATION OF WATER IN THE INTERIOR OF THE

EARTH

The term hydrologic cycle (from the Greek hydro-, meaning "water") refers to the complex system whereby water circulates among its various reservoirs at and near the surface of the Earth. The hydrologic cycle is the global-scale, endless recirculatory process linking water in the atmosphere, on the continents, and in the oceans.

Lead-in

Work in pairs. Look at the following diagrams. What do they show? How would you entitle them? Ask questions to find out more information.

Fig. 1. Hydrologic cycle

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Look at the figure of the hydrologic cycle below. What do the given values mean?

Fig. 3. Hydrologic cycle

What do the arrows on the figure mean? Match the terms (in clouds) with the arrows.

UNDERGROUND

RUNOFF

SURFACE

EVAPORATION

PRECIPITATION

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1. Read the following word formations and learn their pronunciation.

evaporate – evaporation – evaporative precipitate – precipitation – precipitable accumulate – accumulation – accumulative infiltrate – infiltration – infiltrated

circulate – circulation – circulatory – recirculatory store – storage – stored

saturate – saturation – saturated retain – retaining

charge – recharge – discharge

2. Read the text “Hydrologic cycle”. Pay attention to the diagram. Do the exercises after the text.

Fig. 4. Diagram of the hydrologic cycle

Hydrologic Cycle

The term hydrologic cycle (from the Greek hydro-, meaning "water") refers to the complex system whereby water circulates among its various reservoirs at and near the surface of the Earth. These reservoirs include the oceans, the atmosphere, underground water, surface water, glaciers, and the polar ice caps. The hydrologic cycle pervades our terrestrial existence, playing a key role in many natural phenomena. It is directly coupled to the Earth's energy cycle, because solar radiation combines with gravity to drive the global circulation of

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water. This circulation, in turn, plays an important role in the heat balance of the Earth's surface.

The hydrologic cycle is also closely linked to the geosphere and its rock cycle. Water erodes geologic materials, and the breakdown of these materials releases many chemical constituents that in turn define the chemical nature of the water. Water can also build geologic formations, through both chemical and mechanical depositional processes. Water is essential to all life forms in the planetary biosphere. Even the slightest differences in the volumes and chemical compositions of natural waters can have a tremendous impact on biologic communities. As such an essential natural resource, water is of major concern in local, regional, and international law, and has been at the root of many international conflicts.

(Patricia A.Maurice Earth Systems:Processes and Issues, 2000,Cambridge University Press)

3. Match the English term with the Russian one.

4. Match the terms with their definitions.

5. Fill in the gaps with the missing words. Don’t change the form given.

Water in liquid and solid form covers most of the 1._______of the Earth. By a complex process powered by 2._________ and the action of solar energy, an endless exchange of water, in 3. _________, liquid, and solid forms, takes place between the 4. __________, the oceans, and the crust. Water 5.

___________ in the air and in the oceans, as well as over and below the surface of landmasses. The 6. ____________of water in the planet is uneven. General patterns of circulation are present in the atmosphere, the oceans, and the landmasses, but regional features are very irregular and seemingly random in detail. Therefore, while causal relations underlie the overall process, it is believed that important elements of chance affect local 7. _______events.

(Encyclopedia of Science and Technology)

6. For questions 1–10 read the text below. Use the words in the box to the right of the text to form one word that fits in the same numbered space in the text. The exercise begins with an example (0).

7.  You are going to hear a report about the hydrologic cycle. Before you listen, discuss the following questions.

1. Try to guess what percentage of water is concentrated in oceans, glaciers and ice caps.

2. The world per capita use of water in 1975 was about 185,000 gal/yr. And the total human use of water was about 1015gal/yr. What do you think is world use of water nowadays?

8.  Listen to the tape to see if you were right. For questions 1–7 decide whether the statements are true or false.

1.The evaporation of water from the oceans, freshwater sources, plants, and soils is the natural process, which we call the hydrologic cycle.

2.The water in the atmosphere cycles slowly.

3.Water transportation from distant mountains through aqueducts and groundwater pumping cause precipitation increase in semi-arid cities.

4.40 % of water that falls by precipitation on land every year returns to the subsurface runoff.

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5.Watershed is the fundamental unit of the landscape.

6.Drainage basin is the antonym of catchment.

7.More than 99 % of Earth’s water in its natural state is generally suitable for beneficial human use.

8.All our freshwater resources are produced by only 0,001 % of the total water on Earth.

9.Water can be found at a number of locations at or near Earth’s surface.

10.The residence time of water may be only 9 days.

9.  You are going to hear a conversation between two students. Listen and choose the best title. The notes and terms will help you to understand the conversation better.

WATER IN OUR LIFE

THE COMPOSITION

OF WATER

THE WATER CYCLE

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NOTES

You see – видишь ли

Getting down on paper – записываю

Kind of – что-то вроде

You know what? – Знаешь что?

Wait a tick – Подожди минутку

Fire away – Начинай

To get the figures – записать цифры

Mind you – Слушай внимательно

I’ve got that – Я понял

Go on, will you? – Продолжай же!

You know – знаешь ли

That’s incredible – невероятно

Did you get it all down? – Ты все записал?

My pleasure! – Всегда готов помочь!

Have a good day. – Всего хорошего.

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10.  Look at these incomplete sentences from the conversation between

Susan and Nick and try to remember who said them. Write S for Susan and N for Nick. Then listen to the complete sentences and fill in the missing words.

1.On water? Well, I’m working on it right now. …….. ……… ……..

……… the most essential facts.

2.You know what? There’ s something that might be of interest. It’s from a ….. ….. ……

3.Mind you, it’s about …. ….

4.But how does it happens? First, it …. …. ….., lakes, rivers, soil and plants.

5.Wait a tick. Did you say …. …. ….?

6.That’s right. And …. …. …. and ice into the atmosphere.

7.Second. The sun supplies the energy needed for …. …. …..

8.Well. Water then returns to the Earth as …. …. …..

9.You see, you may also write as … … …. if you like.

10.What about energy release by …., ….. and ….?

11. Listen to the dialogue for the third time if necessary and answer the following questions.

1.What article is Nick writing?

2.What information does Susan give to Nick?

3.What are the forms of water that Susan names?

4.What figures does Susan cite?

5.When will Nick’s article go to press?

12.Discussion – You have to give a lecture on “Hydrologic cycle”. Use the keys and diagram.

Keys:

1.Atmospheric water in circulation

2.Formation of storm clouds

3.Precipitation (snow, rain, hail, etc.)

4.Evaporation of precipitation in transit and moisture diffusion

5.Net precipitation on Earth surface

6.Snow storage and melt

7.Infiltration

8.Deep percolation

9.Ground –water flow and storage

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10.Overland flow and depression

11.Evaporation of intercepted and surface water

12.Evapotranspiration

13.Surface storage in lakes and reservoirs

14.Evaporation from lake surfaces

15.Surface streams

16.Evaporation from streams

17.Ground-water exchange from channel storage (base flow and return)

18.Ground-water exchange from channel storage (base flow and return)

19.Ground-water flow to ocean

20.Ground-water flow to ocean

21.Storage in the ocean

22.Evaporation from ocean surfaces

Fig.5. Diagram Water flow scheme of the hydrologic cycle.

13. Now look at the keys for 45 seconds, try to learn the terms. Close your course book and write down the words. Be honest! The person who has more words is the winner.

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14. Look at the schematic illustration of the hydrologic cycle for 30 seconds and then try to draw it. Afterwards ask your partner to describe it.

Fig.6. Schematic illustration of the hydrologic cycle

15. Work in groups and discuss your opinions. Can your group reach an agreement? Read the quotation of the famous hydrogeologist B.L.Lichkov and share your ideas.

“The circulation of natural water on the planet, although not as yet completely understood, must be recognized by all as critically significant for hydrogeology, and for the land areas; the primary significance must be given to their moisture content. Thus, a new hydrogeology must be constructed on three principles – the unity of water, its circulation, and the moisture content of the land. In a word, the circulation of water is one of the cornerstones of modern hydrogeology”

(B.L. Lichkiov)

STAGE 1 – group work responding to problem discussion. During these stage, each group will discuss the problem separately.

STAGE 2 – sharing ideas of response to the problem. One person from each group should move to another; so that each group has a member with different information. Now the members of each new group share their ideas. STAGE 3 – now each of you should jot down all the information you remember.

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Jig-saw plan (1–2 minute) short one-point talk

Multi-point conversation (5 minutes)

16.Now prepare a presentation “The Hydrological Cycle” for the Student Science Conference. The following plan and phrases will help you.

Plan

1.Plan and carry out your presentation.

2.Define the subject of your presentation.

3.Think of the introduction of your presentation.

4.Try to anticipate questions during the preparation of your presentation.

USEFUL PHRASES AND EXPRESSIONS

INTRODUCTION.

The subject of my presentation is…

What I’m going to talk about today is….

I’d like to give you a brief overview of….

The reason I am here today is to talk about…

STRUCTURING

I’ve divided my topic into (three) main sections…..

My presentation will be in (three parts)…

First of all, then, after that, lastly, finally.

MOVING TO A NEW POINT

Turning now to…..

What I’d like to talk about now is…

Now I would like to describe…

Now let’s move on to the next point which is…

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SUMMARIZING AND CONCLUDING

To sum up…

To recapitulate what I’ve been saying…

So. To go over the main points again…

I’d like to conclude by saying.

ENDING A PRESENTATION

Thanking you in advance.

If there are any questions, I’ll be pleased to answer them.

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REFERENCES

1.Encyclopaedia of Science and Technology.

2.Fetter, C.W. (1994). Applied Hydrogeology, New York. MacMillan.

3.Kitkova, N.G. (2004). What is the Earth Made of? Moscow.

Manager.

4.Maurice, P.A. (2000). Earth Systems: Processes and Issues.

Cambridge University Press.

5.Meissner, R. (2002). The Little Book of Planet Earth. New York,

Inc.

6.Pinniter, E.V. (1993). Hydrogeology. Cambridge.

7.Болсуновская Л.М., Демченко В.Н. Учебно-методическое

пособие по аннотированию и реферированию научнопопулярных текстов на англ. яз. для студентов, магистрантов и аспирантов тех. вузов. – М.: Изд-во ТПУ, 2005.

INTERNET RESOURCES

www.en.wikipedia.org

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GEOECOLOGY

I.А. Matveenko

UNIT 1

GEOECOLOGY

The biosphere is a complex system of energy use and material cycling. This system functions on energy flowing from the Sun and it gives off energy (primarily as heat) to space.

Lead-in

Fill in the spidergram with the word associated with geoecology.

Geoecology

Explain these connections.

2. Read the text, do the exercises.

The idea of biosphere appeared more than a century ago, but at first it found a little application, until it was developed by the Russian scientist V.I. Vernadsky. It is his concept of the biosphere that we accept today.

The first living cell emerged between 4 billion and 3.8 billion years ago. At present biosphere includes vast numbers of plants, animals, and other lifeforms of our planet, many of them are yet to be discovered. Biosphere is a relatively thin life-supporting layer around the Earth containing living organisms, which is strongly influenced in its composition, structure and energetic by the living organisms. The part of the biosphere containing the highest concentration of living matter – the Earth’s thin and fragile “film of life” – varies from a few meters in deserts and tundra to a hundred meters in a tropical forest region and oceans.

The biosphere is a complex system of energy use and material cycling. This system functions on energy flowing from the Sun and it gives off energy (primarily as heat) to space.

We can divide the biosphere into two parts, living and nonliving, or biotic and abiotic. The biotic part of the biosphere consisting of fauna and flora is known to be called biota. We can further divide the abiotic portion into three parts: the solid Earth or lithosphere, liquid water or hydrosphere, and the atmosphere.

Ecology is a branch of science which deals with the world of nature – including its human component – at certain levels of biological organization. It is the study of the living organisms interactions with each other and with their environment. Particular concern of the ecologists is with the “higher” levels of life organization: from populations to biosphere. The functional unit

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in ecology is the ecosystem because it comprises all interactions of communities with both their living (biotic) and their nonliving (abiotic) environments.

Ecology is a multidisciplinary science. Facts about ecological systems are drawn from biology, geology, chemistry, physics, and other sciences. Originally ecology was considered to be environmental biology. Modern ecology has to deal with environmental problems caused by human activities.

Geoecology is an interdisciplinary science, probably best translated as environmental sciences. Geoecology is not a synonym for physical geography. It is not dealing solely with the abiotic aspects of ecology. Geoecologists are rather “specializing in interdisciplinarity”, studying the interactions and interrelations abundant in our environment. Geoecologists work in the industry, for municipal, regional or federal authorities, in universities and research institutes, in foreign aid programs, and as freelance consultants or engineers. Broad education combined with high-quality specialized training allows geoecologists to work in fields such as environmental analytics, waste disposal, contaminated sites remediation as well as agriculture and forestry.

People have always affected the natural environment. But the population growth along with the industrial world economy during the last two centuries has increased the magnitude, complexity and rate of these modifications. Today environment is not just modified by human action: it is radically transformed. Global satellite observations of the Earth have revealed that about 60 % of land surface is to some extent damaged by industrial, agricultural, and other human activities, whereas no more than 40 % of land remains intact.

Humankind is entering a new era in its evolution characterised by a new relationship with nature. Understanding of how biosphere works, and how it reacts to the global environmental change is of fundamental importance.

(Положинцев Б. И. Introduction to ecology. СПб., 1999) 3. Find the synonyms for the following words in the text.

To influence, to include, large, to emerge, to change, mankind, to release, field of science, to be concerned with.

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4. Translate the following word groups.

Global satellite observations, industrial world economy, tropical forest region, living organisms interaction, life organization levels, atmosphere layers, nature balance, population growth.

5. Suggest as many word combinations as possible.

(A)layer (thick, of water, around the Earth, of gas, outer, thin, containing living matter);

(B)environment (clear, physical, parts of, modified, healthy, biotic, damaged, intact);

(C)interactions (between, humankind, nature, stable, communities, global, constant, living organisms, environment).

6.State the functions of “it” in the following sentences. Translate them into Russian.

1.It is Vernadskiy’s concept of the biosphere that geoecologists use today.

2.Today environment is not just modified by human action: it is radically transformed.

3.It is rather topical to study the living organism interactions with each other and with their environment.

4.Understanding of how biosphere works, and how it reacts to the global environmental change is of fundamental importance.

5.It is the “higher” levels of life organization: from populations to biosphere that is of particular concern for geoecologists.

6.It is important to research all interactions of communities with both their living (biotic) and their nonliving (abiotic) environments.

7.Translate it into English.

a)Современная концепция биосферы была разработана русским ученым В.И. Вернадским более 50 лет назад (present-day, develop).

Биосфера – это слой вокруг Земли, который преобразован живыми организмами (transform).

Биосфера – слой вокруг Земли, который содержит все живое вещество на нашей планете (contain).

Жизнь на Земле возникла около 3.8 миллиарда лет назад

(emerge).

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b) Биосфера – это сложная система преобразования энергии и круговорота веществ (cycling).

Биосфера «работает» на энергии, поступающей в нее от Солнца

(run on energy).

Толщина слоя биосферы, содержащего наивысшую концентрацию живого вещества, варьируется от нескольких до сотен метров (film of life, vary from … to).

c) Геоэкология – междисциплинарная наука, основанная на экологии, геологии, биологии и многих других науках (interdisciplinary).

Взаимодействие человека с природой имеет глобальный и постоянный характер (interaction).

Человек воздействует на окружающую среду и изменяет ее

(affect).

Биосфера реагирует на эти воздействия (react).

d) Сегодня окружающая среда коренным образом преобразована в результате деятельности человека (radically, as a result of).

Около 60 % природных экосистем суши в той или иной степени разрушено в результате сельскохозяйственной, промышленной и других видов деятельности человека (to some extent, damage).

Не более 40% суши еще осталось нетронутой (intact).

8. Read the text below, use the word given in capitals at the end of each line to form a word that fits in the space in the same line.

of our planet if we want to (10) … a better world for our ensure grandchildren.

9. What are the subjects of the following sciences?

10.Here are some definitions. What are they? Complete the sentences.

…is the layer around the Earth in which all living organisms exist.

…is the sum total of all liquid and frozen water on or near the Earth’s surface.

…is a region of gases, airborne particles, and water vapour enveloping the Earth.

…is the solid Earth with rocks, soils, and sediments on its crust.

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11.Answer the questions.

1.How do you define biosphere?

2.What is biota?

3.When did the first living cells appear on the planet?

4.What are the limits of the “film of life”?

5.What does modern ecology deal with?

6.What is geoecology?

7.What fields can geoecologist work in?

8.What major factor has increased the intensity and scale of the biosphere transformations over the past two centuries?

9.Do you think the biosphere transformations caused by human activity are reversible?

12. Listen to the interview with a senior research engineer called Dr.

Michael Blomberg. Dr. Blomberg gives his opinions on future trends in science and technology.

1.What predictions does Dr. Blomberg make about technological progress? Make a list.

2.Classify these predictions in three columns according to how strongly Dr. Blomberg expresses his belief that they will happen.

3.What questions does the interviewer put to Dr. Blomberg?

4.Now prepare three questions that you would ask Dr. Blomberg if you were present at the interview.

5.Do you agree with Dr. Blomberg’s ideas? Say what developments you foresee in science and technology over next fifty years.

(Johnson C.N. & D. General Engineering. Prentice Hall, Europe,

1998)

13. Work in pairs. Discuss the following quotations about ecological problems.

1.Nature pardons no errors. (R.W. Emerson. Essays)

2.Our remedies oft in ourselves do lie which we ascribe to heaven.

(W. Shakespeare. All’s Well That Ends Well)

3.As soils are depleted, human health, vitality and intelligence go with them. (Bromfield Louis Writer (1896–1956)).

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4.Only when the last tree is cut; only when the last river is polluted; only when the last fish is caught; only then will they realize that you cannot eat money. (Indian proverb).

5.Man has lost the capacity to foresee and to forestall. He will end by destroying the earth. (Albert Schweitzer).

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UNIT 2

THE IMPACT OF MINING AND OIL EXTRACTION ON THE

ENVIRONMENT

Coal, oil and gas – fossil fuels – are called conventional fuels because people are accustomed to using them. Today, approximately 80 % of the energy consumed worldwide comes from burning petroleum, natural gas, and coal. However, coal is the dirtiest fuel to burn because it has many impurities which influence the environment.

Lead-in

Discuss the questions.

1.What impacts of mining and mineral extraction on the atmosphere, hydrosphere and biosphere do you know?

2.What stages of mineral extraction from the subsurface do you know?

Comment upon the following statements. How do you think they are connected with the theme of the lecture?

1. In its broadest ecological context, economic development is the development of more intensive ways of exploiting the natural environment.

~Richard Wilkinson

2. Waste is a tax on the whole people.

~Albert W. Atwood

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waters, and the biosphere.

components is one of the most serious sources of contamination of soils, beneficiation of minerals and the separation and refining of their various deposit will add greatly to these enrichments. The mining and subsequent elements in the vicinity of mineral deposits, mining and extraction of the Although there are likely to be significant natural enrichments of several

deposits.

media such as soil, sediments and waters has been used to locate mineral measurement of the concentrations of various metals and non-metals in the the soils, waters, sediments, plants, etc., close to the deposit. Indeed, Such naturally occurring high concentrations are reflected in the chemistry of represent concentrations of several elements well above crustal abundance. level at which they can be profitably extractable. As such these deposits Mineral deposits represent concentrations of an element or elements to a

2.Read the text, do the exercises.

1. Pay attention to the pronunciation of the following words.

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Humans have extracted minerals, particularly the metalliferous ores, since ancient times, and the extraction and refining of metals have played a major role in human development. The mining and processing of minerals have increased through time, due to population growth and the greater utilization of raw materials for manufacture. Many areas of past mining activity, in both the Old and New Worlds, bear witness to these extractions in the form of abandoned workings and extensive waste tips. Modern mineral extraction technology is generally far more efficient than past practices, and in many countries such processes are heavily regulated to limit the degree of contamination from extractive industries. However, historical mineral extraction involved less efficient technologies and in those times virtually no environmental regulations were in place. Long-abandoned mineral workings are currently the cause of serious environmental pollution in many countries.

A large number of different materials are extracted from the Earth ranging from fuels such as oil and coal, industrial minerals such as clays and silica, aggregates for building and roadstone, and minerals for fertilizers as well as sources of non-metals. However, the major cause of concern is the metalliferous ores that are used as sources of metals and metalloids.

The extraction and subsequent processing of ores can be summarized as follows:

Mining → crushing/grinding

→concentration of ore mineral

→smelting/refining.

Ores are extracted from the Earth by either subsurface mining, open pit surface techniques, or in a few cases by solution mining, which carries with it risk of groundwater pollution. Both subsurface and surface extraction result in waste material, which is generally piled on the surface in the vicinity of mine. However, while such waste piles, which frequently contain ore minerals, are sources of environmental contamination, it is the subsequent processing of the ores that result in the greatest environmental problems.

The crushing and grinding (comminution) of mineral processing has the objective of separating the ore minerals from the waste, generally referred to as gangue. To effect separation, the mined ore is finely crushed to liberate individual ore mineral grains to enable concentration of the sought after ore mineral. The very fine waste material left after this concentration process is referred to as tailings, and this material can contain, along with the gangue minerals, residual amounts of the ore minerals and can be a serious source of

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