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2. What is magma?
3. What is lava?
4. How does magma differ from lava?
5. Lava is emitted in two ways. What are they?
6. What are three distinct parts of magma?
7. What is the name of the liquid portion of magma? What is it composed of?
8. The solid components in magma are silicate minerals, aren’t they?
9. What is the name of the gaseous components of magma?
10. What are the most common volatiles found in magma?
11. When deeply buried magma bodies crystallize, the remaining volatiles collect as
hot, water-rich fluids, don’t they?

Task 4. Complete the following sentences from the text in Task 3.
1. … is composed mainly of mobile ions of the eight most common elements found
in Earth’s crust.
2. The solid components (if any) in magma are … minerals.
3. The gaseous components of magma are called … .
4. The most common volatiles found in magma are … .
5. When deeply buried magma bodies crystallize, the remaining volatiles collect as
… that migrate through the surrounding rocks.

Task 5. Find English equivalents for the following (see the text). Try to
build up your own sentences with them.
Вулканічні гірські породи; траплятися на різних рівнях земної кори; підніматися
до поверхні; виверження попілу; частково розплавлена гірська порода;
утворюватись (складатися) з силікатів; тверда речовина (твердий компонент);
кристалізуватися з розплавленої речовини; остання стадія охолодження;
кашоподібна речовина, що має кристалічну структуру; мати тенденцію
відокремлюватись від розплавленої речовини; виштовхувати магму з повітряного
клапану.

Task 6. Give a short summary of the text from Task 2.

Grammar focus
Infinitive
Task 1. Translate the sentences into Ukrainian paying special attention to
the underlined infinitives.
1. Volatiles tend to be most abundant near the tops of magma reservoirs.
2. When magma rises (or the rocks confining the magma fail) a reduction in pressure
occurs and the dissolved gases begin to separate from the melt, forming tiny
bubbles.
3. At temperatures of 1000 °C and low near-surface pressures, these gases can
quickly expand to occupy hundreds of times their original volumes.
4. Because of the high viscosity of silica-rich magma, a significant portion of the
volatiles remain dissolved until the magma reaches a shallow depth, where tiny
bubbles begin to form and grow.
5. To summarize, the viscosity of magma plus the quantity of dissolved gases and the
ease with which they can escape largely determine the nature of a volcanic
eruption.
6. To explore this idea, a pioneering investigation into the crystallization of magma
was carried out by N. L. Bowen in the first quarter of the 20th century.

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