Environmental- Ch 16. Mining

Evaporites most commonly form in

• arid regions where rates of evaporation are high.

• rain forests where rates of evaporation are low.

• cold regions that receive significant snowfall.

• an area with frequent volcanic activity.

Which of the following are minerals that contain valuable substances?

• native minerals

• ore minerals

• gangue minerals

• longwalls

Which of the following is NOT a characteristic of a mineral?

• naturally occurring

• atoms in random geometric patterns

• usually an inorganic solid

• orderly internal structure

Which of the following is NOT one of the ways that ore minerals may form?

• cooling of magma

• circulation of hydrothermal solutions through rocks

• flooding of empty streambeds and rivers

• evaporation of water that contains salts

What is one property that may be used to distinguish metallic from nonmetallic minerals?

• cost to extract

• value

• carbon content

• electrical conductivity

What must hot subsurface waters contain in order to be considered hydrothermal solutions?

• crystallized minerals

• dissolved minerals

• gangue minerals

• inorganic solids

Gangue minerals

• are valued for their rarity and durability.

• have no commercial value.

• are the most difficult to mine.

• are native elements.

The first step in surface coal mining is

• to remove and set aside the soil that covers the area to be mined.

• to use heavy equipment to take core samples.

• to test to see if quarrying would be more effective.

• to make cuts in the coal for easier removal.

Dredging streambeds may be an effective technique for mining

• salt

• coal

• gold

• sulfur

Acid mine drainage

• harms or kills aquatic life.

• purifies streams.

• causes acid rain.

• is unregulated in the United States.