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processes that form and modify them is basic to locating additional supplies of many important
resources.

Task 3. Copy out all the names of rocks mentioned in the text. Transcribe and
translate them. Are cement and aggregate kinds of rock?

Task 4. Answer the following questions, using the vocabulary from Task 1.
1. What does most of Earth consist of?
2. How does the volume of sedimentary rocks in Earth’s crust compare to igneous and
metamorphic rocks?
3. Where is sedimentary rock situated mostly?
4. What information does sediment provide geologists with?
5. Are sediments and sedimentary rocks also the primary reservoir of groundwater?
6. Why are sedimentary rocks important?

Task 5. Find English equivalents for the following (see the text). Try to build up
your own sentences with them.
Складатись з вулканічних та метаморфічних порід; оцінювати; тверда поверхня
Землі; бути покритим осадовими породами; на вершині (гребені) серединно-океанічних
хребтів; складати малий відсоток земної кори; містити копалини; забезпечувати основною
інформацією; значна частка нашої електроенергії; основні джерела енергії; будівельна
промисловість; основний резервуар ґрунтових вод.

Task 6. Look at Figure 2.1. The diagram outlines the portion of the rock cycle that
pertains to the formation of sedimentary rocks. Weathering, transportation, deposition,
and diagenesis represent the basic processes involved. Using the information about the
basic processes? Talk about the formation of sedimentary rocks.

 Weathering involves the physical disintegration and chemical decomposition of pre-existing
igneous, metamorphic, and sedimentary rocks. Weathering generates a variety of products,
including various solid particles and ions in solution. These are the raw materials for
sedimentary rocks;
 Soluble constituents are carried away by runoff and groundwater. Solid particles are
frequently moved downslope by gravity, a process termed mass wasting, before running water,
groundwater, wind, and glacial ice remove them. Transportation moves these materials from the
sites where they originated to locations where they accumulate. The transport of sediment is
usually intermittent;
 Deposition of solid particles occurs when wind and water currents slow down and as glacial
ice melts. The word sedimentary actually refers to this process. It is derived from the Latin
sedimentum, which means “to settle,” a reference to solid material settling out of a fluid (water
or air). The mud on the floor of a lake, a delta at the mouth of a river, a gravel bar in a stream
bed, the particles in a desert sand dune, and even household dust are examples.
 The deposition of material dissolved in water is not related to the strength of wind or water
currents. Rather, ions in solution are removed when chemical or temperature changes cause
material to crystallize and precipitate or when organisms remove dissolved material to build
shells;
 As deposition continues, older sediments are buried beneath younger layers and gradually
converted to sedimentary rock (lithified) by compaction and cementation. This and other
changes are referred to as diagenesis, a collective term for all of the changes (short of
metamorphism) that take place in texture, composition, and other physical properties after
sediments are deposited.