Volcanoes

19. The world's largest lava dome is: A. Lassen Peak, California B. Mount St. Helens, Washington C. Craters of the Moon, Idaho D. Yellowstone, Wyoming E. Mauna Loa, Hawai'i

A. Lassen Peak, California

4. The type of volcanic hazard that involves a mudflow made of ash is called a: A. lahar B. tsunami C. pyroclastic flow D. debris avalanche E. lava bomb

A. lahar

11. The largest volcano on Earth is also the tallest mountain on Earth (measured from base to top). The volcano is called (1) ___________ and it is a type of (2) ___________. A. (1) Mauna Loa (2) stratovolcano B. (1) Mauna Loa (2) shield volcano C. (1) Kilauea (2) stratovolcano D. (1) Kilauea (2) shield volcano E. (1) Mauna Loa (2) composite volcano

B. (1) Mauna Loa (2) shield volcano

7. A 16 million-year-old analog to the 251-million-year-old Siberian Traps is the: A. eruption of Mount St. Helens B. Columbia River Flood Basalts C. Idaho batholith D. Sierra Nevada batholith (Yosemite) E. eruption of Mount Mazama

B. Columbia River Flood Basalts

26. The cities of Seattle and Tacoma are at risk from lahars that could be produced during an eruption of: A. Mount St. Helens B. Mount Rainier C. Mount Hood D. Mount Shasta E. Lassen Peak

B. Mount Rainier

15. In the list below, choose the correct match of volcano and corresponding volcano type. A. Kilaeua / stratovolcano B. Mount St. Helens / stratovolcano C. Mauna Loa / stratovolcano D. Mayon / shield volcano E. Mount Rainier / shield volcano

B. Mount St. Helens / stratovolcano

5. What major American city is at greatest risk for the above type of hazard? A. San Francisco B. Seattle C. Portland D. New York E. Idaho Falls

B. Seattle

20. A volcano that has never erupted in historic times but which may still erupt one day is said to be: A. active B. dormant C. extinct D. in remission E. asleep

B. dormant

16. Lava bombs, lapilli and volcanic ash are all types of: A. lava B. tephra C. magma D. pyroclastic flows E. Nike sportswear

B. tephra

23. The most active volcano in the Cascades is (1) __________ but the largest known eruption that occurred here in pre-historic times was the eruption of (2) __________. A. (1) Crater Lake (2) Mt. St. Helens B. (1) Mt. St. Helens (2) Lassen Peak C. (1) Mt. St. Helens (2) Mt. Mazama D. (1) Mt. Mazama (2) Mt. Tehama E. (1) Mt. Shasta (2) Mt. St. Helens

C. (1) Mt. St. Helens (2) Mt. Mazama

18. After an eruption, a volcano may start to push new magma up into the crater. The evidence of this is the development of a (1) _________, the world's largest example of which is (2) __________: A. (1) caldera (2) Crater Lake, Oregon B. (1) cinder cone (2) Craters of the Moon, Idaho C. (1) lava dome (2) Lassen Peak, California D. (1) tuff ring (2) Diamond Head, Hawai'i E. (1) spatter cone (2) Mauna Loa, Hawai'i

C. (1) lava dome (2) Lassen Peak, California

9. Low viscosity lava is a characteristic of (1)_________ eruptions, which commonly form a low, gently sloping volcano type called a (2)_________. A. (1) explosive (2) shield volcano B. (1) explosive (2) stratovolcano C. (1) nonexplosive (2) shield volcano D. (1) nonexplosive (2) stratovolcano E. (1) nonexplosive (2) composite volcano

C. (1) nonexplosive (2) shield volcano

21. About how many potentially active volcanoes are there in the western United States? A. 5 B. 10 C. 20 D. 50 E. 100

C. 20

27. Which Cascades volcano is actually the world's largest lava dome that sits inside the caldera of the ancient volcano called Mount Tehama? A. Crater Lake B. Mount Shasta C. Lassen Peak D. Mount Hood E. Mount St. Helens

C. Lassen Peak

1. How many active volcanoes are there in the world? A. about a million B. around 10,000 C. around 1,500 D. around 800 E. less than 100

C. around 1,500

28. Which of the following features were NOT produced when Mount St. Helens erupted in 1980? A. lahar B. lateral blast C. pahoehoe lava flows D. pyroclastic flow E. Plinian column

C. pahoehoe lava flows

2. The type of volcanic hazard that involves a huge cloud of extremely hot tephra that rushes down the slope of a volcano is called a: A. lahar B. tsunami C. pyroclastic flow D. debris avalanche E. lava bomb

C. pyroclastic flow

3. The type of volcanic hazard that resulted in the deaths of the inhabitants of Pompeii in 79 AD was a: A. lahar B. gas cloud C. pyroclastic flow D. debris avalanche E. lava flow

C. pyroclastic flow

8. The last time Earth experienced a prolonged period of flood basalt volcanism was 16 million years ago. What happened as a result of this event? A. most of the species in the world went extinct B. Siberia was completely covered in basalt C. the Columbia River basalt was formed D. Crater Lake formed in Oregon E. the islands of Hawai'i were created

C. the Columbia River basalt was formed

12. The largest active volcano on Earth is: A. Lassen Peak, California B. Mount St. Helens, Washington C. Mount Mazama, Oregon D. Mauna Loa, Hawaii E. Yellowstone, Wyoming

D. Mauna Loa, Hawaii

24. Which Cascades range volcano has erupted 14-15 times in the past 4000 years? A. Mount Mazama B. Mount Rainier C. Mount Hood D. Mount St. Helens E. Lassen Peak

D. Mount St. Helens

10. Which of the following is NOT a characteristic of a nonexplosive eruption? A. shield volcano B. low-viscosity lava C. typically mafic lava D. Plinian column E. examples in Hawaii, Iceland and Galapagos

D. Plinian column

17. If a volcano erupts explosively and then collapses into the void left by the emptying of the magma chamber below the mountain, it produces a wide and deep circular hole called a: A. crater B. cinder cone C. lava dome D. caldera E. maar crater

D. caldera

25. Before Mount St. Helens erupted in 1980, the last Cascades volcano to erupt was: A. Mount Mazama B. Mount Rainier C. Mount Hood D. Mount St. Helens E. Lassen Peak

E. Lassen Peak

13. When Mount St. Helens (1980) and Mt. Pinatubo (1991) erupted, they both produced a high, vertical plume of ejected pyroclastic material called a: A. lateral blast B. pyroclastic flow C. tephra cloud D. lapilli eruption E. Plinian column

E. Plinian column

22. Which western US volcano last erupted about 70,000 years ago? A. Mount Mazama B. Mount Rainier C. Mount Hood D. Craters of the Moon E. Yellowstone

E. Yellowstone

14. Volcanoes with steep slopes that form from the accumulation of viscous lava and pyroclastic flows are: A. shield volcanoes B. stratovolcanoes C. composite volcanoes D. either A or B above E. either B or C above

E. either B or C above

29. Which of the following statements about the 1980 eruption of Mount St. Helens is FALSE? A. it was the 15th or so eruption of Mt. St. Helens in the past 4000 years B. the eruption was triggered by a gigantic landslide on the side of the volcano C. the eruption started off as a lateral blast and then formed a Plinian column D. prevailing winds carried ash eastwards across Washington and Idaho E. the eruption came as a complete surprise to volcanologists

E. the eruption came as a complete surprise to volcanologists

6. Which of the following combinations is NOT a correct match of a volcanic hazard and a corresponding example? A. ejected lava bombs (e.g., Galeras, Colombia) B. pyroclastic flow (e.g., Pompeii in AD 79) C lava flow (e.g., Goma, Democratic Republic of Congo) D. lahar (e.g., Armero, Colombia in 1985) E. toxic gas cloud (e.g., Kilauea, Hawaii)

E. toxic gas cloud (e.g., Kilauea, Hawaii)