Chapter 6 Rock Review
1. What do all types of rocks have in common? They are all made of Minerals
2. List the three types of sedimentary rock, what they’re made of and how they’re formed.
a) clastic – compaction and cementation of rock fragments
b) organic – compaction and cementation of pieces of plant or animal
c) chemical – evaporation or precipitation of dissolved minerals
3. Igneous rocks are classified according to composition and texture
4. Rocks formed from lava cooling rapidly on the surface are called extrusive and they form small grains. List
one example: basalt
5. Describe the color, consistency and the minerals that make up mafic magma. Name an example. Gabbro,
Basalt, Scoria
color –Dark
consistency -thin & fast
minerals- Mg & Fe
6. Rocks formed from magma cooling slowly underground are called intrusive and they form large grains. List
one example: granite.
7. Describe the color, consistency and the minerals that make up felsic magma. Name an example. granite,
pumice, obsidian
color - Light
consistency - thick & slow
minerals- silica
8. What size crystals do rocks have that cool extra fast? Name an example: none – pumice/obsidian
9. What are the three types or rocks and how does each form?
a) Igneous – solidification of magma
b) Sedimentary – compaction/cementation of sediments
c) Metamorphic – heat & pressure
10. Which clastic sedimentary rock contains the largest sediment size? Conglomerate
11. What is the relationship between the length of time molten magma takes to cool and the size of the crystals
in the rock formed by the magma?
Slow cooling = Big Crystals; Fast cooling = Tiny Crystals; Extra fast cooling = No crystals
12. What is the difference between magma and lava? Magma – found underground; Lava – found above
ground
13. Visible horizontal layers found in sedimentary rock are called strata.
14. What kind of rock would be formed near a river? Sedimentary
15. Metamorphic rocks are changed by heat & pressure.
16. What porous igneous rock can float on water? Pumice
17. The 3 main types of rocks are classified according to their texture and the processes that form them.
18. What characteristic is used to classify a rock as shale, sandstone, or conglomerate? Sediment or grain size
19. What is the name of the organic sedimentary rock made from the calcite in seashells? Limestone/Coquina
20. Why do glassy textured rocks like obsidian show no grains? Cooled extra fast
21a. How are granite and obsidian similar? They are both felsic in composition
21b. How are obsidian and basalt similar? They are both extrusive IR
22. What is the name of a very abundant felsic intrusive IR? Granite
23. What is an igneous intrusion? A rock mass that forms when magma cools inside Earth’s interior. Also
called a pluton.
24. What is the rock cycle? A repeated series of events where rocks change form
25. Which rocks can have ripple marks and fossils? Sedimentary
26. Can any type of rock form from any type of rock? Yes
27. What is a geode? A round, hollow SR with minerals trapped inside.
28. Which type of rock has foliation? Metamorphic
What is foliation? Bands or stripes of minerals in Metamorphic Rocks
Name 3 examples of rocks with foliated texture. Slate, Schist, Gneiss
29. What is contact metamorphism? The process that forms metamorphic rocks over small areas. Rock is
heated when it comes in contact with magma or lava.
30. What is a batholith? Largest of all plutons that form the cores of many of Earth’s mountain ranges.
Exposed through uplift and erosion.
5. Laccolith
1. Volcanic Neck
2. Volcano
3. Batholith
4. Sill