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15. Fill in the gapes with to make up (to be made up of), to constitute, to consist of, to compose (to be composed of).
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15. Fill in the gapes with to make up (to be made up of), to constitute, to consist of, to compose (to be composed of).
Don’t mix up
| составлять | состоять из |
| to make up to compose to constitute | to be made up of to be composed of to consist of |
1. The Earth’s crust ______ rocks. 2. Rocks ______ the Earth’s crust. 3. Most of these rocks ______ minerals. 4. Minerals ______ the rocks. 5. Minerals ______ chemical elements. 6. A few minerals ______ single element, such as native gold or silver. 7. Most minerals, however, ______ two or more chemical elements united in such a way that the product of the union differs greatly in its properties from those of the elements composing it. 8. Quartz ______ the largest part of most sands and sandstones. 9. Most sandstones ______ grains of quartz.
16. Match the words and word-combinations from the first column with the words and word-combinations that have the same meaning from the second column.
| 1. to occur 2. to combine 3. to consist of 4. to make up 5. constituent 6. abundant 7. to possess 8. to exhibit 9. gemstone 10. to be exposed 11. heat 12. various 13. environment 14. combination | a) to constitute b) precious stone c) different d) unit e) to show f) to have g) conditions h) to be subjected i) component j) to unite k) to be present l) to be composed of m) widely spread n) high temperature |
17. Replace the underlined words with their synonyms.
Minerals are compounds, which means they are 1) combinations of elements. Most minerals are stable only 2) in the environment in which they formed. If minerals, which formed at the surface of the earth, are deeply buried or 3) subjectedto heat and pressure, they change. Minerals 4) unite with each other to form rocks. For example, granite 5) consists of the minerals feldspar, quartz, mica, and amphibole in varying ratios. A 100 of the several thousand known types of minerals 6) constitute the main 7) components of rocks. The quartz is one of the most 8) abundant minerals found on earth. It is found in granite and other rocks, such as sandstone.
18. Listen to the text ‘Feldspars’ and answer the questions.
1. What chemical elements does feldspar consist of?
2. What does the term “silicate” stand for?
3. What rocks is feldspar commonly found in?
4. What rocks is feldspar extracted from?
5. What color can feldspars have?
6. What luster do feldspars have?
7. What fact in geology demonstrates the significance of feldspar?
8. What does the color of feldspar depend on?
19. Translate into English.
1. Минералы – это твердые природные вещества, составляющие горные породы.
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2. Минералы – это природные химические соединения, имеющие определённый химический состав и кристаллическую структуру.
3. Хотя большинство минералов встречается в природе в виде химических соединений, некоторые минералы, например, золото, серебро, медь, встречаются в виде самородных элементов.
4. Минералы образуются в результате природных физико-химических процессов в земной коре.
5. Минералы стабильны только в условиях той среды, в которой они образовались.
6. Если минерал, образовавшийся в глубине земли, окажется на поверхности, где давление, температура и влажность другие, то он разрушится.
7. Если глинистый минерал, образовавшийся на поверхности земли, подвергнуть воздействию высокой температуры и давления, он превратится в слюду.
8. Существуют некоторые минералы, например, кварц, которые остаются стабильными при широком диапазоне условий.
9. Полевые шпаты – это группа широко распространенных породообразующих минералов, составляющих около 60 % земной коры.
10. Полевые шпаты встречаются в вулканических, осадочных и метаморфических породах.
11. Кварц – один из самых распространённых минералов в земной коре, породообразующий минерал большинства магматических и метаморфических пород.
PART 3. GEMSTONES
19. Read the text and translate it into Russian.
Diamond is a rare naturally occurring mineral composed of carbon. Diamond is a fascinating mineral. It is chemically resistant and it is the hardest known natural substance. Diamond also has special optical properties such as a high index of refraction and high luster. These properties help make diamond the world's most popular gemstone.
Diamonds are not native to Earth's surface. Instead, they form at high temperatures and pressures that occur in Earth's mantle about 100 miles down. Most of the diamonds that have been discovered were delivered to Earth's surface by deep-source volcanic eruptions.
Ruby and sapphire are both gems of the mineral corundum. Both of these gems have the same chemical composition and the same mineral structure. Trace amounts of impurities determine if a gem corundum will be a brilliant red ruby or a beautiful blue sapphire.
Some gem-quality corundum contains trace amounts of chromium. A very small amount of chromium gives corundum a pink color. Larger amounts of chromium increase the color saturation of the stone and produce a gem with a deeper red color. To be considered a ruby, a corundum should have a color between orangey red and a slightly purplish red. The most desirable color is a pure vibrant red. Trace amounts of iron and titanium can develop a blue color in corundum. Blue corundum is known as sapphire.
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Emerald is the deep green color variety of the mineral known as beryl. Diamonds, sapphires, rubies, and emeralds are considered to be the most precious stones.
Aquamarine is the second most popular gem beryl. Aquamarine has a distinct blue color. The stones that are richly colored are the most desirable.
(from: http: //geology. com/gemstones/)
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