McMaster University EARTH SC 2gg3 Quiz 2 1)The most dangerous area during the pyroclastic flow is: The top of the mountain The air above the mountain The bottom of the valley The mountain   What kind of material is most likely to fall in a rotational slide? Homogeneous, cohesive material Rounded sand grains in the slope Loose, dry soils Elongated boulders with smoothly rounded sides   The name of acidic volcanic smog is: Pumice Lahar Carbon dioxide Vog   What is daylighted surface or layer? A weak layer, sloping downward toward a road cut or hillside at a somewhat gentler slope than the hillside A part of the bedrock that is exposed at the surface   A layer that becomes exposed by excavation of a road cut None of theses   Rhyolite magma typically erupts in what form? Thin, fast-moving lava flows Thick, fast-moving lava flows Lahars Fine ash   Which of the following statements about volatiles is true? Magmas that contain little water erupt violently Water exposed to high temperatures of magma become a solid Water content determines the violence of a volcanic eruption All of these are true   What is a volcanic surge? An underground magma flow A mixture of hot volcanic ash, water and steam that rushes down the volcano’s slope A high speed, violent ash-rich shock wave A tremendous earthquake   What is the term describing the process of gases coming out of solution, when the pressure drops and magma rises? a) Expire Express Exsolve None of these   Volcanic mudflows, or lahars are caused when which of the following combine? Lava and rocks Ash and lava Water and ash Lava and water   Which of the two main volcanic gases is heavier than air, collects in low areas and can asphyxiate people or animals if it is in high concentrations? a) Hydrogen Water vapor Ethane Carbon dioxide   If you see a large volcano with very gentle slopes, what kind of volcano is it and what rock is it likely to be made of? a) A stratovolcano made of andesite A cinder cone made of basalt A shield volcano made of basalt lava flows A stratovolcano made of basalt lava flows   Where are quick clays most common? Alaska, Canada, Scandinavia Central America and Africa California Colorado and Wyoming   What type of volcano consists of layers of lava, fragmental debris and ash? Shield volcano Cinder cone Stratovolcano Continental caldera   Old landslides are NOT normally reactivated by                                       

McMaster University

EARTH SC 2gg3

Quiz 2

1)The most dangerous area during the pyroclastic flow is:

1. The top of the mountain
2. The air above the mountain
3. The bottom of the valley
4. The mountain

2. What kind of material is most likely to fall in a rotational slide?

1. Homogeneous, cohesive material
2. Rounded sand grains in the slope
3. Loose, dry soils
4. Elongated boulders with smoothly rounded sides

3. The name of acidic volcanic smog is:

1. Pumice
2. Lahar
3. Carbon dioxide
4. Vog

4. What is daylighted surface or layer?

1. A weak layer, sloping downward toward a road cut or hillside at a somewhat gentler slope than the hillside
2. A part of the bedrock that is exposed at the surface

3. A layer that becomes exposed by excavation of a road cut
4. None of theses

5. Rhyolite magma typically erupts in what form?

1. Thin, fast-moving lava flows
2. Thick, fast-moving lava flows
3. Lahars
4. Fine ash

6. Which of the following statements about volatiles is true?

1. Magmas that contain little water erupt violently
2. Water exposed to high temperatures of magma become a solid
3. Water content determines the violence of a volcanic eruption
4. All of these are true

7. What is a volcanic surge?

1. An underground magma flow
2. A mixture of hot volcanic ash, water and steam that rushes down the volcano’s slope
3. A high speed, violent ash-rich shock wave
4. A tremendous earthquake

8. What is the term describing the process of gases coming out of solution, when the pressure drops and magma rises? a) Expire

2. Express
3. Exsolve
4. None of these

9. Volcanic mudflows, or lahars are caused when which of the following combine?

1. Lava and rocks
2. Ash and lava
3. Water and ash
4. Lava and water

10. Which of the two main volcanic gases is heavier than air, collects in low areas and can asphyxiate people or animals if it is in high concentrations? a) Hydrogen

2. Water vapor
3. Ethane
4. Carbon dioxide

11. If you see a large volcano with very gentle slopes, what kind of volcano is it and what rock is it likely to be made of? a) A stratovolcano made of andesite

2. A cinder cone made of basalt
3. A shield volcano made of basalt lava flows
4. A stratovolcano made of basalt lava flows

12. Where are quick clays most common?

1. Alaska, Canada, Scandinavia
2. Central America and Africa
3. California
4. Colorado and Wyoming

13. What type of volcano consists of layers of lava, fragmental debris and ash?

1. Shield volcano
2. Cinder cone
3. Stratovolcano
4. Continental caldera

14. Old landslides are NOT normally reactivated by                                        .

1. Adding water
2. Earthquakes
3. Piling heavy rocks on the lower part of the slope
4. Steepening the slope by removing material at the lower part of the slope

15. What causes a big bulge to slowly grow on the flank of an active Mount St. Helens volcano?

1. Thick lava flows pile up around the vent
2. A huge gas bubble released from the magma inflates it
3. The hot magma melts older ash, causing it to expand
4. Rising magmas is pushing it up

16. How does pahoehoe lava differ from aa lava?

1. Pahoehoe is full of gas holes and aa is solid lava
2. Pahoehoe is rhyolite and aa is basalt
3. Pahoehoe is rope and aa is rubbly
4. Pahoehoe is basalt and aa is andesite

17. One way in which water CANNOT be removed from a wet slope that may slide is to              .

1. Plant trees and shrubs to increase evapotranspiration
2. Pump water out from a well
3. Insert perforated pipes into the slope to help drain it