(TEST 2) Earth Science, Lecture pt 4 (ch 12)

Question 1

What is Halite (NaCL) used for?

Answer 1

It is used as a ground for table salt and it helps to de-ice
roadways in winter

Question 2

What is diamond (C) used for?

Answer 2

It’s used as a great cutting tool

Question 3

What is a mineral resource?

Answer 3

It’s a rock, mineral, or element that is important to humans

Question 4

What is a mineral resource footprint?

Answer 4

The amount of minerals needed to support a lifestyle

Question 5

What are mineral and rock resources considered to be at the human time scale?

Answer 5

Non-renewable

Question 6

What do people do to address the issue of supplies being exhausted?

Answer 6

They oppose building new mines near their home

Question 7

What is ore deposit?

Answer 7

A body of rock or sediment whose concentration of some material is sufficiently high that the deposit is economically feasible to extract

Question 8

What is an example of ore deposit?

Answer 8

Gold mining

Question 9

What is a mineral (or ore) reserve?

Answer 9

A deposit that is economical to extract under current conditions

Question 10

What does high/low grade ore deposit describe?

Answer 10

It describes the enrichment level of the ore deposit

Question 11

What is the enrichment factor?

Answer 11

The ratio of a resource’s necessary concentration for profitable mining to its average concentration in Earth’s crust

Question 12

What are some characteristics of diamond (Kimberlite/Lamproite) pipes?

Answer 12

• Forms at depths of 120-200 km in upper mantle
• Brought to the surface by sudden and violent eruptions
• Relatively rare: low-frequency events and not all pipes have diamonds

Question 13

What are some characteristics of intrusive layered deposits?

Answer 13

• Early-stage magmatic process where crystal settling occurs during cooling of a magma to create layered ore deposits
• Typically contain metallic-rich minerals such as: chromium, titanium, and vanadium

Question 14

What are some characteristics of hydrothermal deposits?

Answer 14

• Late-stage magmatic process where deposits are concentrated in veins or small dikes.
• Gold and silver prevalent in hydrothermal deposits
• Disseminated deposits

Question 15

What are the characteristics of disseminated deposits?

Answer 15

• Low-grade deposits where ore minerals are widely dispersed
• Common minerals include: copper, tin, and tungsten

Question 16

What are the characteristics of massive sulfide deposit?

Answer 16

• Formed along mid-ocean ridges
• Reactions between seawater and basaltic rocks create
  hydrothermal fluids rich in copper, lead, and zinc

Question 17

What are some characteristics associated with regional metamorphism?

Answer 17

• High temperature and pressure associated with deep burial of rocks and tectonic activity
• Can change the mineralogy and texture
• Produces ores of asbestos, talc, graphite, and other non-metallic deposits

Question 18

What are some characteristics associated with contact metamorphism?

Answer 18

• Intrusion of igneous materials
• Heat, pressure, and chemically active fluids of the cooling magma interact with the country (or host) rock

Question 19

What are placer deposits?

Answer 19

Streams transport and sort
material according to size and
density in a certain area

Question 20

What is residual ore?

Answer 20

An accumulation of valuable minerals, formed by the natural removal of undesired constituents of rocks or conversion

Question 21

What are iron minerals precipitated out of?

Answer 21

Shallow seas

Question 22

What are branded iron formations?

Answer 22

Alternating layers of quartz
and iron oxide minerals

Question 23

What are evaporite deposits?

Answer 23

Dissolved material in water precipitate out of solution as the waters evaporate

Question 24

When do marine deposits form?

Answer 24

When marine basins become isolated by tectonic activity

Question 25

What are non-marine deposits typically driven by?

Answer 25

Climatic variations

Question 26

What are the two ways of surface mining?

Answer 26

• Open-pit mine
• Surface mine

Question 27

What is open-pit mine?

Answer 27

Excavating large volumes of low-grade deposits

Question 28

What is a strip mine?

Answer 28

Mineral deposits lie parallel to the surface; overburden is
scraped away

Question 29

Why do we use underground mining?

Answer 29

Used today when removal of overburden is too expensive or
disturbance of surface not allowed

Question 30

What are some ways of mineral processing?

Answer 30

• Physical separation
• Smelting
• Leaching

Question 31

What is mine tailing?

Answer 31

Large piles of
non-economical rock and
processed ore

Question 32

Mineral resources increases as _____ development increases

Answer 32

Economic

Question 33

What are strategic minerals?

Answer 33

Minerals considered critical by a country but that must be imported in significant quantities

Question 34

What is the general mining act of 1872?

Answer 34

Prospectors could purchase public lands for $5/acre and then extract the resources without paying any royalties to the government

Question 35

What is the clean air act of 1970 and clean water act of 1972?

Answer 35

Minimized pollution from modern mining operations

Question 36

Mining of minerals fueled what revolution?

Answer 36

The industrial revolution

Question 37

What is acid mine drainage?

Answer 37

It’s the term for the leachate that drains from tailings and underground mines

Question 38

Why do some acid mine drainage have a blue/greenish color?

Answer 38

It’s due to copper precipitates

Question 39

Most acid mine drainage contains….?

Answer 39

Dissolved iron

Question 40

What are some impacts of underground mines?

Answer 40

• They can create a lot of void spaces that can collapse suddenly (also known as sinkholes)
• They can also cause the ground to lower gradually (also known as subsidence)