Exam 2 Practice Quiz

33. Why do volcanoes such as Mount St Helens erupt explosively, whereas others like Kilauea are relatively effusive? D

a. Continental volcanoes, like Mount St. Helens, tend to be more explosive than oceanic volcanoes, like Kilauea, because they have less water around them.​ b. Mount St Helens is above a mid-ocean ridge and Kilauea is not c. Kilauea has more volatiles than Mount St Helens and volatiles reduce the strength of the eruption d. The magmas associated with Mount St Helens are more viscous than those associated with Kilauea because they have more silica

19. Which response best represents the conditions of contact metamorphism? A

a. Low pressures, shallow burial, and heat supplied by a nearby magma body b. High pressure, deep burial, and temperatures raised by Earth's internal heat c. Heat generated by shearing and mechanical movements along faults d. shallow depths, and temperatures and pressures so high that the rock partially melts

10. How do physical and chemical weathering processes work together? A

a. Physical weathering increases the surface area of the rock while chemical weathering weakens the attachments between the grains b. Physical and chemical weathering both increase surface area and weaken the attachments between grains equally c. Physical and chemical weathering only work separately; they don't work together d. Chemical weathering increases the surface area of the rock while physical weathering weakens the attachments between the grains

34. The rhyolitic magma that formed the volcanic rock associated with the Yellowstone calderas formed from the melting of the mantle. B

a. True b. False

16. Certain factors determine the type of deformation that occurs in a rock. Of the following, which is NOT one of those factors? A

a. age of the rock b. pressure c. temperature d. composition of the rock e. deformation rate

21. In which setting would hydrothermal metamorphism be most likely? A

a. at shallow depths below an oceanic ridge or rift zone b. at shallow depths along major transform faults in the continental crust c. at great depths in the crust where two continents collide d. at shallow depths beneath the volcanic arc where magma chambers produce high heat

35. Which of the following is a volcanic precursor that can be used as advanced warning of possible volcanic activity? C

a. bulging and tilting of the surface of the volcano b. seismic activity and gas emissions c. seismic activity, bulging and tilting of the surface of the volcano, and increased gas emissions d. increased gas emissions e. seismic activity

31. Which of the following is NOT a typical environment in which a metamorphic rock forms? B

a. burial to great depths b. solidification of lava c. squeezing by tectonic forces d. heating adjacent to underground magma

11. The main cause of caldera collapse is... D

a. collapse of the north flank by landslides b. removal of magmas that form pillow basalt c. a fissure eruption that allows the shield volcano to split into two or more parts d. collapse of the roof of a magma chamber as magma erupts

9. How could you distinguish a chemical sedimentary rock from an igneous rock? C

a. color b. hardness c. composition d. texture e. grain size

20. Folds are most often created through what type of stress? A

a. compression b. tension c. shear d. confining

27. If stress causes a temporary change in the shape or volume of rock, but the rock returns to its original shape/size once stress is removed, the rock has been put under what type of strain? B

a. ductile deformation b. elastic strain c. brittle deformation d. permanent strain

17. Regional metamorphism usually occurs... A

a. during mountain building at a convergent plate boundary b. in basins associated with convergent boundaries c. during mountain building at a divergent plate boundary d. in basins associated with divergent boundaries

32. Volcanic mudflows (lahars) are common on stratovolcanoes because... B

a. hot mud commonly erupts from their central craters b. large amounts of rain and snowmelt mix with loose ash on steep slopes c. such volcanoes form preferentially in rainy tropical locations

14. The Black Hills of South Dakota are a large dome that has been deeply eroded. Where would you find the youngest exposed rocks associated with the dome? B

a. in the deepest part of the dome b. along the outside edges of the dome c.in the center of the dome d. in the highest part of the dome e. it would depend on the structure of the dome

24. What is the difference between "joints" and "faults" in rocks? A

a. joints are fractures that form due to brittle expansion or stretching of rocks, while faults are fractures where the rocks on one side have moved relative to the other side due to many different types of stresses b. faults form first but if the deformation continues, then joints will begin to form in the rock to show that the rock unit is about to break apart entirely c. the terms describe the same thing d. faults are fractures that form due to brittle expansion or stretching of rocks, while joints are fractures where the rocks on one side have moved relative to the other side due to many different types of stresses

2. Felsic magmas/lavas are ___________ viscous than basaltic magmas/lavas because they contain a ____________ percentage of silica. D

a. less; higher b. less; lower c. more; lower d. more; higher

7. Flood basalt eruptions are fed by... A

a. long fissures/dikes b. central vents/craters c. lava tubes

15. Which of the following make it more likely that a rock will bend instead of break? D

a. low confining pressure, low temperatures, soft rocks b. high confining pressure, low temperatures, hard rocks c. high confining pressure, high temperatures, hard rocks d. high confining pressure, high temperature, soft rocks e. low confining pressure, high temperatures, hard rocks

26. Metamorphism can change the texture of a rock by... D

a. making rounded edges more sharp with new crystal growth b. making sharp edges more rounded and smooth c. producing smaller crystals d. aligning the minerals

6. What tectonic setting is interpreted to be the cause of volcanism at Yellowstone? A

a. movement of the North American Plate over a mantle plume b. magma that is coming up along a bend in a transform fault c. subduction along the coast of the Pacific Northwest d. a large meteorite impact that struck the area 100 years ago

1. Which of the following plate boundaries is least likely to produce stratovolcanoes? B

a. ocean-continent convergent boundary with subduction (Andes) b. continent-continent convergent boundary with a high mountain range (Himalayas) c. ocean-ocean convergent boundary with subduction (Philippines)

4. Which of the following processes are NOT considered to be chemical weathering? C

a. oxidation b. dissolution c frost wedging d. hydrolysis

25. Magma formation at convergent plate boundaries is caused by... C

a. partial melting due to raising the temperature b. partial melting due to increasing the pressure c. partial melting due to adding water and lowering the melting temperature of the rocks in the crust d. partial melting due to lowering the pressure

8. The two main processes by which sediment is produced are.. A

a. physical and chemical weathering b. transportation and deposition c. subduction and melting

23. Which of the following brittle deformation is the result of tensional stress? C

a. reverse faulting b. strike-slip faulting c. normal faulting d. shearing e. folding

5. Potentially explosive stratovolcanoes are most common above... C

a. rift zones b. transform zones c. subduction zones

22. Which of the following is NOT one of the three ways that temperature can be raised enough to cause metamorphism to occur? C

a. sediment burial b. magma intrusion c. injection of water d. tectonic burial

18. Clastic sedimentary rocks are classified primarily on the basis of... A

a. sediment size b. location of these sediments c. sedimentary structures d. depth of burial

29. Major types of stress are... A

a. shear, tension, and compression b. compression, ductile, and brittle c. compression, strain, and deformation d. shear, ductile, tension, brittle, and compression e. ductile and brittle

20. Reverse faults are associated with... C

a. tensional stresses that characterize divergent plate boundaries b. compressional stresses that characterize divergent plate boundaries c. compressional stresses that characterize convergent plate boundaries d. horsts and grabens in the western United States e. tensional stresses that characterize convergent plate boundaries

13. Why would a plume of solid silicate rock rising slowly from deep in the mantle begin melting as it neared the base of the lithosphere? C

a. the rock heats up and expands at lower pressure, causing it to melt b. the lowered pressures cause rapid heat loss accompanied by melting c. temperatures remain high as lowered pressures allow the rock to melt

3. What is the relationship between viscosity and temperature? B

a. there is no relationship between viscosity and temperature b. viscosity increases with decreasing temperatures c. viscosity decreases with decreasing temperatures d. viscosity increases with increasing temperatures

12. Shield volcanoes commonly involve... C

a. viscous lava flows b. volcanic domes c. fluid lava flows d. pyroclastic flows e. All of these choices are correct

28. What are the important processes involved in lithification? B

a. weathering and metamorphism b. compaction and cementation c. crystallization and weathering d. metamorphism and crystallization