ТЕКСТА General Information on Mining
As has been said, mining refers to actual ore extraction. Broadly speaking, mining is the industrial process of removing a mineral-bearing substance from the place of its natural occurrence in the Earth's crust. The term "mining" includes the recovery of oil and gas from wells; metal, non-metallic minerals, coal, peat, oil shale and other hydrocarbons from the earth. In other words, the wo± done to extract mineral, or to prepare for its extraction is called mining.
The tendency in mining has been towards the increased use of mining machinery so that modern mines are characterized by tremendous capacities. This has contributed to: 1) improving working conditions and raising labour productivity; 2) the exploitation of lower-grade metal-bearing substances and 3) the building of mines of great dimensions.
Mining can be done either as a surface operation (quarries, opencasts or open pits) or by an underground method. The mode of occurrence of the sought-for metallic substance governs to a large degree the type of mining that is practised. The problem of depth also affects the mining method. If the rock containing the metallic substance is at a shallow site and is massive, it may be economically excavated by a pit or quarry-like opening on the surface. If the metal-bearing mass is tabular, as a bed or vein, and goes to a great distance beneath the surface, then it will be worked by some method of underground mining.
Working or exploiting the deposit means the extraction of mineral. With this point in view a number of underground workings is driven in barren (waste) rock and in mineral. Mine workings vary in shape, dimensions, location and function.
Depending on their function mine workings are described as exploratory, if they are driven with a view to finding or proving mineral, and as productive if they are used for the immediate extraction of useful mineral. Productive mining can be divided into capital investment work, development work, and face or production work. Investment work aims at ensuring access to the deposit from the surface. Development work prepares for the face work, and mineral is extracted (or produced) in bulk.
The rock surfaces at the sides of workings are called the sides, or hi coal, the ribs. The surface above the workings is the roof in coal mining while in metal mining it is called the back. The surface below is called the floor.
Unit 8_____________________________ •_______________ 193
The factors such as function, direct access to the surface, driving in mineral or in barren rock can be used for classifying mine workings:
I. Underground workings:
a) Long or deep by comparison with their cross-section may
b) Large openings having cross dimensions comparable with
c) Production faces, whose dimensions depend on the thick
8. Укажите, какие предложения соответствуют содержанию текста. Подтвердите свои ответы фактами из текста.
1. As a rule, the term "mining" includes the recovery of oil and
2. The increased use of mining machinery has greatly contributed
3. It is quite obvious that the problem of depth is not always
4. Productive workings are usually used for the immediate ex
5. Underground workings are driven in barren rock or in mineral.
6. A shaft is a vertical underground working which is long and
7. The surface above the mine working is usually called the floor.
8. The rock surfaces at the sides of mine workings arc called the ribs.
9. Ответьте на следующие вопросы:
1. What is mining?
2. What has contributed to the better working conditions of the
3. What factors influence the choice of the mining method?
4. In what case is useful mineral worked by open pits?
5. Are exploratory workings driven with a view to finding and proving
6. What is the difference between development and production
7. What main factors are used for classifying mine workings?
8. What do the dimensions of production faces depend on?
10. а) Найдите • правой колонке русские эквиваленты следующих слов и сочетаний слов:
1. direct access to the surface
2. open-cast mining
3. tabular (or bedded) deposits
4. oil well
5. underground workings
6. cross-section of a working
7. production face
8. the roof of the mine working
9. to drive mine workings in
10. to affect the mining method
а) нефтяная скважина
б) проходить горные выработки по
в) влиять на метод разработки
г) прямой доступ к поверхности
д) пластовые месторождения
е) открытая разработка
ж) поперечное сечение выработки
з) подземные выработки
к) кровля горной выработки
6) Найдите в правой колонке английские эквиваленты следующих слов сочетаний слов:
1. способствовать чему-л.
2. размер ствола
3. извлекать, добывать (уголь)
4. штреки и квершлаги
5. пустая порода •
6. вообще говоря
7. удалять, перемещать (крепь,
8. с целью ...
9. подготовительные работы
а) thickness of a seam
б) shaft dimension
в) with a view to
г) to contribute to smth.
д) development work
е) to remove (timber, overburden,
ж) drifts (gate roads) and crosscuts
з) generally speaking
11. Подберите из списков А и Б близкие но значению слова:
6. crop out (outcrop)
7. barren rock
12. broadly speaking
13. take into consideration
б) take into account
в) make better
r) waste (country) rock
ж) generally speaking
и) open pit к) dimension л) side м) grade н) guarantee
Unit 8 __________________________________ 195
12. Переведите предложения, обращая внимание на перевод условных
1. If the geological and prospecting indications are known, it is
2. Providedthe geologists make use of proper prospecting
3. On condition thatdifferent types of ores are to be tested
4. Unlessthe face is directly connected to the upper level, the
13. Заполните пропуски соответствующей формой глагола в скобках:
1. Unless metamorphic rocks (to be studied) carefully, geolo
2. If the mass of magma (to be) large, the rate of cooling will
3. If the earth (to be made) of the same material from the sur
4. Provided geological conditions permit, efficient coal face
5. We really will not survive unless we (to start) working on
6. If you learned to type, you (to find) the job quite easily.
7. If he were here, I (can explain) to him myself.
8. They would have been here by now if they (to catch) the
9. I (not to believe) it possible, if I hadn't seen it happen.
14. Соедините главные предложения с придаточными:
1. It is possible to use trenches a) providedat some distance
a waste bed which must be separated from mineral.
2. Mine workings are considered 6) if the latter is blended with
3. Rock will not easily cleave в) on condition thatthe
thickness of overburden is small.
4. A bedded deposit is to be r) unlessits schistose structure
5. Bituminous coal will improve д) if they are driven with a
6. The cutter-loader will cut coal above the floor
e) ifit lies at a great distance from the surface.
©2015- 2021 megalektsii.ru Все материалы представленные на сайте исключительно с целью ознакомления читателями и не преследуют коммерческих целей или нарушение авторских прав.