Test yourself

Task: Tell whether the sentences are true or false. Correct the false ones.

1. The three principal divisions of Earth’s surface are the continents, the mountains and the ocean basins.

2. The continents are remarkably mountainous features.

3. The features of continents can be extensive, flat stable areas as well as uplifted regions of deformed rocks.

4. The youngest mountains are located principally in two major zones: in the circum-Pacific belt and in the belt which extends eastward from the Alps through Iran and the Himalayas and then dips southward into Indonesia.

5. Older mountains are also found in Russia.

6. Within the stable interiors are areas known as mountain belts.

7. Stable platforms exist in which highly deformed rocks, like those found in the shields, are covered by a relatively thin veneer of sedimentary rocks.

8. The continental margin may include the continental shelf, the continental slope, and the continental rise.

9. Between the continental margins and oceanic ridges lie the deep-ocean basins. Parts of the deep-ocean basins consist of incredibly flat features called the continental shelf.

10. The most prominent feature on the ocean floor is the oceanic or mid-ocean ridge.

Unit 4 magma Part 1

Task 1. Read and memorize the following words:

convective upwelling - конвекційний апвелінг (підйом глибинних вод на поверхню)	subduction - субдукція, підсування (однієї тектонічної плити під іншу)
accompany by - супроводжуватись	ascend - підніматися; досягати
magnify - збільшуватись	confining - обмежуючий; обмежувальний
increase - збільшення	curve - гнутися, згинатися, вигинатися
seafloor –ложе моря або океану	descend into – переходити у
content - вміст	exist - існувати
decompression – зниження тиску	in volume – в об’ємі
trigger – грати роль спускового механізму	reduce – знижувати, зменшувати
volatile - летючий, той, що швидко випаровується	rift apart - розколювати, розщеплювати; розколюватися, розщеплюватися
сonversely - навпаки

Task 2. Look at Figure 4.1. It is a schematic diagram illustrating a typical geothermal gradient (increase in temperature with depth) for the crust and upper mantle. Also illustrated is an idealized curve that depicts the melting point temperatures for the mantle rock peridotite. Notice that when the geothermal gradient is compared to the melting point curve for peridotite, the temperature at which peridotite melts is everywhere higher than the geothermal gradient. Thus, under normal conditions the mantle is solid. Special circumstances are required to generate magma. Study the schematic diagram. It will help you understand increase in temperature better when talking about origin of magma.

Task 3. Read the following text, translate it into Ukrainian.