An active volcano is any volcano that:

An active volcano is any volcano that:

Has not been worn away by erosion

Is currently erupting or has erupted in geologically recent times

Is located on a tectonic plate boundary

Has not erupted recently but is likely to erupt in the future

Question 2

1

point

2. Question 2

[Q#3005]

Which of the following is a type of volcano formed predominantly from hardened basalt lava flows?

Shield volcano

Stratovolcano

Caldera

Cinder cone

Question 3

1

point

3. Question 3

[Q#3006]

Stratovolcanoes are typically composed of alternating layers of:

Volcanic ash and lava

Rhyolite volcanic ash and basalt volcanic ash

Rhyolite lava and basalt lava

Two separate volcanoes that merge to form one

Question 4

1

point

4. Question 4

[Q#3009]

A measurable change in the heat flow of a locality on the earth is taken to be an indication of:

The impending occurrence of an earthquake along a fault in the next 24 hours

A sudden increase in the rate of radioactive decay in rocks of the subsurface at the locality

The validity of the hydrologic cycle

The probability that a volcano at the locality will erupt

Question 5

1

point

5. Question 5

[Q#3011]

All of the following are somewhat effective means of dealing with volcanic hazards EXCEPT:

Steering the direction of a lava flow

Plugging a volcano's vent

Accurately predicting a volcanic eruption

Cooling a lava front with water

Question 6

1

point

6. Question 6

[Q#3013]

Which of the following statements about lava is TRUE?

Lava is more explosive than magma.

Lava with a high gas content tends to be more explosive than lava with a low gas content.

Lava with a mafic composition is more explosive than lava with a felsic composition.

All of the other choices are true.

Question 7

1

point

7. Question 7

[Q#3015]

A volcanic ash flow (a nuée ardente or glowing avalanche):

Has the potential to incinerate nearby towns

Consists of a muddy mixture of meltwater and lava

Is produced from ash that blows high up into the air before settling back to Earth

Poses little threat to life because the ash is light and cool

Question 8

1

point

8. Question 8

[Q#3017]

A caldera forms:

From a thick layer of cool ash that settles near the volcano

When the magma chamber beneath a volcano drains suddenly during a massive eruption/explosion, and the volcano collapses to form a circular depression

When a river cuts off a meander and leaves a semi-circular lake filled with water

Where a mountain stream deposits an apron of fine sediment at the base of the mountain

Question 9

1

point

9. Question 9

[Q#3019]

The explosion of Mount Saint Helens in 1980:

Is the largest volcanic explosion that is known to have occurred in the geologic record

Is a tiny explosion when compared to the explosion that resulted in the Yellowstone caldera.

Is typical of eruptions of shield volcanoes

Was unrelated to the occurrence of lahars in nearby river valleys

Question 10

1

point

10. Question 10

[Q#3022]

True or false? The burial and destruction of Pompeii by Mount Vesuvius in 79 AD was due to rapidly flowing basalt lava.

True

False

Question 11

1

point

11. Question 11

[Q#3023]

Which volcano tends to have mainly non-explosive eruptions?

Mount Vesuvius, Italy

Mount Pelee, Martinique

Mount Saint Helens, Washington

Kilauea, Hawaii

Question 12

1

point

12. Question 12

[Q#3028]

Which of the following mountain chains is composed primarily of volcanoes formed at an ocean-continent collision zone?

Hawaiian Islands

Andes

Himalayas

Alps

Question 13

1

point

13. Question 13

[Q#3029]

True or false? The products of volcanic eruptions include lava flows and explosively erupted volcanic ashfalls.

True

False