Chapter 4: Rocks Study Guide

Section 4-1 Classifying Rocks (pages 94-97) Name ______Period ____

1. Earth’s crust is made of ______.

2-4. Circle the letters of the characteristics that geologists use to classify rocks.

a.  Texture c. hardness

b.  mineral composition d. color

5. Rocks are made of mixtures of ______and other materials.

6. Geologists can test a rock sample for carbonates by testing it with a(n) ______.

7. True or False? Most rocks can be identified by color alone. ______

8. Particles of minerals and other rocks that make up a rock are called ______.

9. The look and feel of a rock’s surface is its ______.

10-12. Geologists (people who study rocks) describe a rock’s texture based on the grain ______, grain ______, grain ______or in some cases, no grain at all.

13-18. Fill in the concept map below.

19-22. By observing a rock’s color, texture and mineral composition, geologists can determine the rock’s ______, which is how the rock formed. Then geologists can classify the rocks into one of 3 major rock groups: ______, ______& ______.

23-25. Each rock group is formed in a different way. ______rocks are formed as lava

and magma cool. ______rocks are formed when tiny particles are packed together

tightly under a large body of water. ______rocks are formed deep underground when an existing rock is affected by intense heat and incredible pressure, that causes the elements inside the rock undergo a chemical reaction, forming a completely new rock.

Section 4-2 Igneous Rocks (pages 98-101)

26-27. ______rock forms on top of the earth’s surface. The most common type is ______, which makes up much of the ocean floor.

28-29. Intrusive rock forms ______. The most common type is ______, which forms the core of many mountains.

30. The texture of an igneous rock depends on the size and shape of its ______.

Match each igneous rock texture (left column) with the way it forms (right column).

______31. fine-grained a. magma cools in two stages, forming large and small crystals

______32. coarse-grained b. lava cools rapidly, forming small crystals

______33. porphyritic c. magma cools slowly, forming large crystals

34. True or False? Intrusive rocks have smaller crystals than extrusive rocks. ______

35-36. Circle the letter of each sentence that is true about the silica composition of igneous rocks.

a. Igneous rocks that are low in silica are usually dark-colored.

b. An example of an igneous rock which is low in silica is granite.

c. Igneous rocks that are high in silica are usually light-colored.

d. An example of an igneous rock which is high in silica is basalt.

37-39. People throughout history have used igneous rocks for tools and building materials because they are ______, ______and ______.

Section 4-3 Sedimentary Rocks (pages 102-106)

40. True or False? Sedimentary rocks form from particles deposited by people and animals. ______

41. Small, solid pieces of materials that come from rocks or living things are called ______.

42-44.Three forces that can carry sediments are ______, ______and ______.

45-48. When water or wind loosen and carry away fragments or rock, it is called ______. When the sediments settle out of the water or wind, it is called ______.

______is when sediments are pressed together in layers. When dissolved minerals glue sediments together, it is called ______.

49-52. Name 4 examples of sediments. ______

______

53. True or False? It takes millions of years for sedimentary rock to form. ______

Fill in the table below to show how geologists classify sedimentary rocks according to the type of sediments they contain.

Classification of Sedimentary Rock / Type of Sediment It Contains
Clastic Rocks / 54.
Organic Rocks / 55.
Chemical Rocks / 56.

Section 4-4 Rocks From Reefs (pages 107-109)

57. Skeletons of living coral grow together to form a structure called a ______.

58-59. Coral animals absorb the element ______from the ocean water, but their protective outer shell is made from ______.

60-62. Coral animals are very delicate creatures. They cannot survive in waters below ____ meters deep in the ocean because they need sunlight to live. They must also be in ______(temp.) waters, which limits the area where they can survive (but the water can also be too hot). Coral animals are mostly located on the ______coasts of continents because the waves are less destructive.

Section 4-5 Metamorphic Rocks (pages 110-112)

63-64. ______and ______are the forces that cause rocks to change into metamorphic rocks.

65-68. What 4 things change when a rock undergoes metamorphism? ______

______

69. True or False? The deeper a rock is buried in the crust, the less pressure there is on that rock. ______

70. True or False? Geologists classify metamorphic rocks by the arrangement of grains in the rock. ______

71-72. Metamorphic rocks with grains arranged in parallel layers or bands are said to be ______. If the grains are arranged randomly, the rock is said to be ______.

Section 4-6 The Rock Cycle (pages 114-116)

73. The series of processes that slowly changes rocks from one kind to another is referred to as the ______.

74-77. The 4 forces that move rocks through the rock cycle are volcanic ______, ______, ______and ______&______.

78. True or False? All rocks follow the same pathway through the rock cycle. ______