II. Прочитайте текст и выполните задание на понимание текста.

Текст

Sedimentary rocks form a very small proportion by volume of the rocks of the Earth’s crust. About three quarters of the earth’s surface is occupied by the rocks of sedimentary origin.

Sedimentary rocks have been formed by accumulation of solid materials on the Earth’s surface. It is necessary to note that the processes which lead to the formation of sedimentary rocks are going on around us.

Sediments are classed into: a) mechanical, b) chemical, and c) organic. Mechanical sediments are gravel, sand, sandstone, shale etc. Such sediments can be transformed into conglomerates, sandstones and clay schists as a result of the accumulation of materials achieved by the destructive mechanical action of water and wind.

Chemical sediments are the result of deposits or accumulations of substances achieved by the destructive chemical action of water. The minerals as salts, some limestones and iron ores are formed through sedimentation of mineral substances that are dissolved in water.

Organic sediments are limestone, coal, peat etc. Organic sediments have been accumulated by the action of organic decay.

Выберите правильный вариант ответа, который соответствует содержанию текста

1. Sedimentary deposits have been formed…

1). deep in the Earth’s crust;

2). at the surface;

3).inside igneous rocks.

2. Different strata of sediments contain…

1) different substances;

2) the same substance;

3) igneous rocks.

3. Gravel, sand and shale are…

1) chemical sediments;

2) organic sediments;

3) mechanical sediments.

4. Coal peat and limestone are…

1) chemical sediments;

2) organic sediments;

3) mechanical sediments

5. Chemical sediments are…

1) salts and iron ores;

2) sand and shale;

3) peatandcoal.

III. Задания по лексике

Bыберите правильный вариант перевода подчеркнутого словосочетания.

1. The rocks of the Earth’s crust are divided into three main groups.

a) земная кора

b) земная поверхность

с) уплотненные осадки

2. Like gypsum rock salt is formed through sedimentation of mineral substances.

a) любит гипс

b) подобно гипсу

c) нравится гипс

3. Consolidated rocks are very similar to the loose sediments whose particles are firmly cemented to one another by some substance.

a) свободные породы

b) уплотненные породы

с) неуплотненные породы

4. Coal is a stratified deposit that have been developed from plant remains.

a) существующее месторождение

b) обнаженные залежи

с) пластовое месторождение

5. Еxposed rocks were formed at a various depth.

a) изверженные породы

b) обнаженные породы

с) осадочные породы.

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