Ф 03-03 Kasymova Zh. Zh

Practical class №11. Rocks and Minerals
Aims of practical lesson is introduction with types of rocks and minerals
11.1. Lexical terms and word combinations

Granite – гранит

Feldspar – полевой шпат
Hornblende –роговая обманка, роговик
Biotite – биотит (чёрная слюда)
Molten – расплавленный
Beach – морской берег, взморье; отмель
Dune –дюна
Igneous rocks - магматическая горная порода
Metamorphic rocks – метаморфическая горная порода
Sedimentary rocks – осадочная горная порода
Crystallize – вызвать процесс кристаллизации, кристаллизовать
Precipitate – осадок, осаждать
11.2.Reading Passage
The earth is composed of rocks, which are aggregates of small grains or crystals called minerals (Fig. 2-1). Minerals are naturally occurring, relatively pure chemical compounds. Examples of minerals are quartz (SiC2) and calcite (СаСО3). Rocks can be composed of numerous grains or several different minerals. The rock granite, for example, is composed of the minerals quartz, feldspar, hornblende, and biotite. Rocks can also be composed of numerous grains of the same mineral.

The rock limestone consists only of calcite mineral grains. Rocks have been formed throughout the billions ofyears of earth’s history. The same chemical and physicalprocess that form rocks today formed rocksthroughout geological time. The molten lava flowing out a volcano in Hawaii or Italy today is forming lava rock similar to lava rock formed millions and billions of years ago. Ancient sandstone rock composed of sand grains was formed the same way sand is deposited today: along beaches, in river channels, and on desert dunes. There is nothing unusual about ancient rocks. They formed the same way rocks are forming today.

Classification of rocks. Rocks of traps
Three types of rocks make up the earth’s crust: igneous, sedimentary, and metamorphic. Igneous rocks have crystallized from a hot, molten liquid. Sedimentary rocks are composed of sediments that were deposited on the surface of the ground or bottom of the ocean or salts that precipitated out of water. Metamorphic rocks have been recrystallized from other rocks under high temperatures and pressures.
All oil and gas deposits are found in structural or stratigraphic traps. You may have heard that oil is found underground in “pools,” “lakes,” or “rivers.” Maybe someone told you there was a “sea” or “ocean” of oil underground. This is all completely wrong, so don’t believe everything you hear.

Fig 11.1 - Oil Moving Through Pore Space In Sandstone
Most oil and gas deposits are found in sandstones and coarse-grained limestones. A piece of sandstone or limestone is very much like a hard sponge, full of holes, but not compressible. These holes, or pores, can contain water or oil or gas, and the rock will be saturated with one of the three. The holes are much tinier than sponge holes, but they are still holes, and they are called porosity.
The oil and gas become trapped in these holes, stays there, for millions of years, until petroleum geologists come to find it and extract it.
When you hold a piece of sandstone containing oil in your hand, the rock may look and smell oily, but the oil usually won’t run out, and you can’t squeeze sandstone like a sponge! The oil is trapped inside the rock’s porosity.