1. Rocks help to decipher the Earth’s past and understand the processes that have shaped our planet. The Earth is not static but is instead continually regenerating and rearranging itself. As land and rock are formed in one area, they are destroyed in another. According to plate tectonics, the Earth’s surface is broken into several large, rigid plates that move in conjunction with convection currents that operate in the Earth’s interior. The boundaries of these plates are places of intense geological activity—earthquakes, volcanoes, and young mountain ranges all tend to be concentrated along the edges of plates. For this reason, plate boundaries are where many rocks are either created, changed, and/or destroyed.

2. The rocks of the Earth’s surface are classified into three types according to their origin: igneous, sedimentary, and metamorphic.
Igneous rocks are formed by the cooling and crystallization of hot, molten rock material called magma. The word igneous means "formed by fire." Igneous rocks make up about 95 percent of the earth’s crust. Basalt and granite are common igneous rocks.

Sedimentary rocks are formed from weathered material (sediments) carried by water, wind, or ice. Sedimentary rocks are the most common rocks in the upper part of the Earth’s crust. They cover more than two-thirds of the Earth’s surface. Sandstone, shale, and limestone are the common sedimentary rocks.

Metamorphic rocks are formed from preexisting rocks (igneous, sedimentary, or metamorphic) that are transformed by high temperature, high pressure, or both—without melting. The word metamorphic means "changed in form." Marble and slate are common metamorphic rocks

3. Because all three types of rock are composed of one or more minerals, we now focus on minerals and their properties. Minerals are the building blocks of rock. Geologists define a mineral as a naturally formed, generally inorganic, crystalline solid composed of an ordered array of atoms and having a specific chemical composition. Minerals differ from one another in their combination and proportion of elements and/or in the internal arrangement of their atoms.
4. A few minerals, such as gold, copper, and iron, are composed of single elements. Most minerals, however, are compounds of more than one element. Chemical composition and internal crystal structure provide the basis for the classification of minerals. Although sophisticated instruments can be used to determine a mineral’s composition and crystal structure, minerals are most often identified by their easily observable physical properties. The physical properties include crystal form, hardness, cleavage, luster, color, streak, and specific gravity.

Source: Hewitt, P.G., Suchocki, J., & Hewitt, L.A. (1999). Conceptual Physical Science, 2/e., New York, © Paul G. Hewitt, John Suchocki, and Leslie A. Hewitt. An imprint of Addison Wesley Longman, p.533-534

This activity contains 10 questions.

	Match the following terms with their definitions or examples. Using the pull-down menus, match each item in the left column to the corresponding item in the right column. to set or place in order standing or fixed in one place to interpret the meaning of 1.1 decipher A B C 1.2 static A B C 1.3 array A B C

	Match the following prefixes with their meanings. Using the pull-down menus, match each item in the left column to the corresponding item in the right column. before together with back, again, against 2.1 re- A B C 2.2 con- A B C 2.3 pre- A B C

	Match the following terms with their definitions or examples. Using the pull-down menus, match each item in the left column to the corresponding item in the right column. restoring to original strength or properties arranging again existing earlier or before 3.1 regenerating A B C 3.2 rearranging A B C 3.3 preexisting A B C

	Match the following terms with their definitions or examples. Using the pull-down menus, match each item in the left column to the corresponding item in the right column. in conjunction with science that deals with the history of the earth and its life especially as recorded in rocks the circulatory motion that occurs in a fluid 4.1 conjunction A B C 4.2 convection A B C 4.3 geology A B C

	Match the following terms with their definitions or examples. Using the pull-down menus, match each item in the left column to the corresponding item in the right column. formed by or from deposits of sediment formed by solidification of magma change of physical form, structure, or substance 5.1 igneous A B C 5.2 sedimentary A B C 5.3 metamorphosis A B C

	Match the following terms with their definitions or examples. Using the pull-down menus, match each item in the left column to the corresponding item in the right column. existing or situated within the limits or surface of something being or composed of matter other than plant or animal a branch of geology concerned with the formation folds and faults in the earth's crust. 6.1 tectonics A B C 6.2 inorganic A B C 6.3 internal A B C

	Match the following terms with their definitions or examples. Using the pull-down menus, match each item in the left column to the corresponding item in the right column. the quality of a crystallized substance or rock of splitting along definite planes to form by putting together an act of recognizing and noting a fact or occurrence often involving measurement with instruments 7.1 compose A B C 7.2 cleavage A B C 7.3 observation A B C

	Match the following prefixes with their meanings. Using the pull-down menus, match each item in the left column to the corresponding item in the right column. to sit, sink down change into, inside 8.1 sed- A B C 8.2 in- A B C 8.3 meta- A B C

	Match the following with their meanings. Using the pull-down menus, match each item in the left column to the corresponding item in the right column. fire earth together, with 9.1 com- A B C 9.2 geo- A B C 9.3 ignis A B C

	Match the following suffixes with their meanings. Using the pull-down menus, match each item in the left column to the corresponding item in the right column. act or state of, suitable for pertaining to capable of, suitable for 10.1 -age A B C 10.2 -able A B C 10.3 -ic A B C

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