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Task 5. Look at Figure 16.1. It shows classification of common
metamorphic rocks. Using the information from the text and from Figure 3.1 try to
characterize the following rocks:
 mylonite;
 hornfels;
 anthracite.

Task 6. Look at Figure 16.2 and try to guess the names of the rocks A, B, C,
D, E, F. How did you come to those conclusions?

Task 7. Provide a short summary (5-6 sentences) of the text.

TEST YOURSELF

Task 1. Tell whether the sentences are true or false. Correct the false ones.
1. Metamorphism is a process that leads to changes only in the mineral content and
texture.
2. In metamorphism the rock gradually changes.
3. The intensity of metamorphism is different.
4. There are 4 agents of metamorphism.
5. During metamorphism the agents affect rock simultaneously.
6. Gneisses are medium to coarse-grained metamorphic rocks in which platy
minerals predominate.
7. Marble is a coarse, crystalline metamorphic rock whose parent was limestone.
8. Quartzite is a very fine-grained foliated rock.

Task 2. Fill in the gaps in the following summary with the suitable words
and word combinations:
Sedimentary, pressure, mineralogical, metamorphism
1
… is the transformation of one rock type into another. Metamorphic rocks form from
2
preexisting rocks (either igneous, … , or other metamorphic rocks) that have been
3
altered by the agents of metamorphism, which include heat, … and chemically active
fluids. During metamorphism the material essentially remains solid. The changes that
4
occur in metamorphosed rocks are textural as well as … .

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