Impending signs of Volcanic Eruption

1. What do you call the molten rocks found beneath the Earth?

• A. elements

• B. lava

• C. magma

• D. minerals

2. Which of the signs of an impending volcanic eruption refers to the

swelling of volcano that signals the accumulation of magma near its

surface?

• A. gas emission

• B. harmonic tremors

• C. increase in number of earthquake

• D. bulges in the mountain or inflammation

3. People residing near volcanoes may detect premonitory events before a

volcanic eruption. Which of the following senses is not used?

• A. auditory

• B. gustatory

• C. tactile

• D. visual

4. Which toxic gas is released naturally by volcanic activity?

• A. carbon dioxide

• B. carbon monoxide

• C. hydrochloric acid

• D. sulfur dioxide

5. Which of the following substances is responsible for a rotten egg smell?

• A. helium

• B. magnesium

• C. silica

• D. sulfur

6. Which of the following characteristics of magma mainly affects the

explosiveness of a volcanic eruption?

• A. amount

• B. color

• C. silica content

• D. temperature

7. All of the following events indicate an impending eruption except:

• A. a measurable bulge or swelling of the volcano

• B. occurrence of short earthquakes in the region

• C. discovery of new hot springs around the volcano

• D. increased temperature of hot springs around the volcano

8. Which of the following is a parameter used to monitor volcanoes by

observing the surface of the volcano for any changes?

• A. gases

• B. ground deformation

• C. seismic activity

• D. sensory observations

9. Which of the following should be continuously monitored to in a lake

or hot spring around a volcano?

• A. chemical content

• B. temperature

• C. turbidity

• D. all of the above

10. Which of the following events does not indicate an impending eruption?

• A. drying up of hot springs around the volcano

• B. eroded area of the volcano after a heavy rain

• C. drying up of the vegetation around the volcano

• D. variation in the chemical content of the lakes and springs around

  the volcano