Earth Systems Ch 10, 11 Study Guide-KEY
1. A lava flow with a surface of rough, jagged blocks and sharp, angular projections is
called what? AA Flow
2. What factors affect how violently or quietly a volcano erupts? 1) Magma’s composition,
2) magma’s temperature and 3) concentration of dissolved gases in the magma
3. Highly explosive volcanoes tend to have what type of magma? Magma with high silica,
high viscosity and higher gas content
4. What is a volcanic bomb? A piece of semi-molten rock ejected as glowing lava
5. The particles produced in volcanic eruptions are called what? Pyroclastic material
6. Large particles of hardened lava ejected from a volcano are called what? blocks
7. What is the most abundant gas associated with volcanic activity? Water vapor
8. Label the diagram: A=Magma Chamber, B=Vent, C=Lava, D=crater
9. What type of volcano is illustrated in Figure 10-1? Composite Cone
10. Describe a Cinder Cone volcano. 1) They have very steep sides, 2) they are usually less
than 300 meters high and 3) they often occur in groups.
11. The most violent volcanic eruptions are associated with what type of volcano?
Composite cones
12. What is a caldera? A large depression in a volcano.
13. When do lava plateaus form? When fluid basaltic lava flows out of fissures.
14. Structures that form from the cooling and hardening of magma beneath Earth’s surface
are called what? Plutons
15. What is the largest intrusive igneous body called? Batholith
16. A lens-shaped intrusive igneous mass close to Earth’s surface is called a what? Laccolith
17. Describe a batholith. 1) They are intrusive igneous bodies, 2) they are larger than
plutons and 3) they are associated with major mountain ranges.
18. Magma forms when solid rock in the crust and upper mantle does what? Melts
19. Why does magma tends to rise towards Earth’s surface? Because rocks become less
dense when they melt.
20. Most of the active volcanoes on Earth are located in a belt known as the what?
Ring of Fire
21. In general, what is true about the composition of the igneous rocks produced in
association with subduction zone volcanic activity? The rocks are rich in silica
22. Which type of landform develops at plate boundaries where one oceanic plate descends
beneath another? Volcanic Island Arc
23. The Hawaiian Islands are associated with what type of volcanism? Intraplate Volcanism
24. All changes in the original shape and/or size of a rock body are called what?
Deformation
25. Under what conditions do rocks exhibit ductile deformation? High confining pressure
26. What combination of temperature and pressure favors folding rather than faulting?
High temperature and high confining pressure
27. List the three types of rock deformation. 1) Elastic deformation, 2) Ductile deformation
and 3) Brittle deformation
28. Deformation in which the object returns to its original shape and size after the stress is
removed is called what? Elastic deformation
29. The type of deformation in which the object permanently changes size and shape
without fracturing is called what? Ductile deformation
30. A material that undergoes tensional stress tends to (stretch or get shorter)? Stretch
31. List the three types of stress seen in rocks. 1) Shear stress, 2) Tensional stress and 3)
Compressional stress
32. Folding is usually the result of what type of stress? Compressional
33. A fault in which the hanging wall moves down relative to the footwall is a normal fault.
34. What is orogenesis? The processes that produce mountains.
35. How are mountains classified? By the dominant processes that formed them.
36. List the three major types of mountains. 1) folded mountains, 2) fault-block mountains
and 3) volcanic mountains
37. A graben is bound by what type of fault? A normal fault
38. Label the following diagram: A-horst, B-graben
39. What type of faults are shown in Figure 11-1? Normal faults
40. An example of folded mountains can be seen in which mountain range?
The Alps in Europe
41. In a typical fault-block mountain, large blocks of crust are uplifted along normal faults.
42. The Black Hills of South Dakota were formed by what type of orogenesis? upwarping
43. According to Figure 11-2, what type of structure does diagram A represent? A dome
44. In diagram B of Figure 11-2, where would the oldest rock layers be located? At “F”
45. How was the structure formed in diagram A of Figure 11-2?
By upwarping of basement rocks
46. At a continental-continental convergent boundary, what type of mountains result?
Folded mountains
47. What are the 2 major types of mountain ranges that are formed at convergent plate
boundaries? 1) folded mountains and 2) volcanic mountains
48. What type of mountains are produced by ocean-continental convergence? Folded AND
volcanic mountains
49. What type of mountains are most common at divergent plate boundaries? Fault-block
mountains
50. Which of the following are associated with the process of orogenesis at divergent
boundaries? (folded mountains, domes and basins, mountain chains at ocean ridge or
volcanic island arcs) Mountain chains at ocean ridges
51. In mountainous regions, the continental crust is (thinner or thicker than average?)
Thicker than average
52. As erosion removes the tops of mountains, the crust will rise upwards. This is an
example of what? Isostatic adjustment
53. The thickest part of the crust occurs in (old or young mountain ranges?)
Young mountain ranges