Minerals

Minerals that make up rocks, are defined as inorganic substances which occur naturally and have a definite chemical composition and physical properties which vary within known limits. The major properties are colour, crystal form, hardness, cleavage and others. Cleavage is one of the most diagnostically useful mineralogical properties which can be found throughout the mineral.

Minerals of use to man can be grouped into two broad categories: 1) metals, such as aluminium, copper, gold, silver, iron-tin, platinum, chromium, nickel, lead and zinc, and 2) non-metallic minerals, such as diamonds, salt, limestone, cement, sulphur, and asbestos. When minerals occur so that they can be worked at a profit they are called ore deposits. Mineral deposits are seldom equally rich throughout.

Economic minerals are those which are of economic importance and include both metallic and non-metallic minerals. Most minerals consist of several elements. Such elements are oxygen, silicon, titanium, aluminium, iron, magnesium, calcium, sodium, potassium, and hydrogen. They make up more than 99 per cent by weight of all the rock-forming minerals. Of these, aluminium, iron and magnesium are industrial metals. The other metals are present in small quantities, mostly in igneous rocks.

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Вариант 2

1) Обозначьте словообразовательные элементы в следующих словах. Словапереведите:

1. accumulation, 2. investigator, 3. firmly, 4. thickness, 5. originate, 6. biochemical, 7. different, 8. igneous.

2) Подчеркните двойные союзы. Предложения переведите на русский язык:

1. Mechanical sediments can be either consolidated or unconsolidated.

2. Neither faults nor fissures were found by the surveyors.

3. We study both rock mechanics and surveying.

4. Both mining engineers were highly skilled specialists.

3) Употребите глагол ’tohave’ в нужной форме. Предложения переведите на русский язык:

1. They (to have) obtained reliable information on the mineral reserves next week.

2. We (to have) already observed physical weathering in deserts.

3. He is the best student in our group: he (to have) excellent marks in metallurgy and mining.

4. He told me he (to have) never heard about academician A.Y. Fersman before.

4) Подчеркните сказуемые в следующих предложениях. Предложения переведите на русский язык и к предложениям в страдательном залоге задайте общий вопрос:

1. Coal is still the most important fuel.

2. No fissures were found.

3. We say that the method of mining is rational if it guarantees only safety of the men and maximum output of minerals.

4. The shield method of mining is used where short faces are worked.

5. After mining or dredging ores are usually processed, crushed or dried.

6. The drills for making holes have handles.

7. A level is a horizontal road with no direct access to the surface.

8. As a rule open-cast mining is used when the deposit lies near the surface.

5) Подчеркните модальные глаголы и их заменители в следующих предложениях. Предложенияпереведитенарусскийязык:

1. The benches may be separated by thin layers of clay, shale, pyrite or other mineral matters commonly called partings.

2. Modern deposits of Kamchatka volcanoes must be investigated.

3. They were to meet at the Institute at five.

4. One can get higher mining education at a higher mining Institute.

5. You should attend your classes regularly to become a highly qualified specialist.

6. They have to explore those deposits again.

7. He will be able to work as a mining engineer after graduation from the Institute.

8. The students were allowed to use this modern equipment while their practical training.

6) Переведите текст на русский язык со словарем:

Date: 2015-11-14; view: 1588; Нарушение авторских прав