Geology and nonrenewable mineral resources

 How do we find and extract mineral resources from the earth’s crust, and what harmful environmental effects result from removing and using these minerals?... Mantle Hot outer core Inne

Chapter 15

Geology and Nonrenewable Mineral

Resources

Chapter Overview Questions

 What major geologic processes occur within the earth and on its

surface?

 What are nonrenewable mineral resources and where are they found?

 What are rocks, and how are they recycled by the rock cycle?

 How do we find and extract mineral resources from the earth’s crust, and what harmful environmental effects result from removing and using

these minerals?

Chapter Overview Questions (cont’d)

 Will there be enough nonrenewable mineral resources for future

generations?

 Can we find substitutes for scarce nonrenewable mineral resources?

 How can we shift to more sustainable use of nonrenewable mineral

resources?

Updates Online

The latest references for topics covered in this section can be found at the book companion website Log in to the book’s e-resources page at www.thomsonedu.com to access InfoTrac articles

 InfoTrac: Residents discuss towns' deaths Daily Oklahoman (Oklahoma City, OK) August 2, 2006

 InfoTrac: All that glitters: the demand for gold is soaring Jane Perlez, Kirk Johnson New York Times, May 8, 2006 v138 i14 p12(6)

 InfoTrac: In Old Mining Town, New Charges Over Asbestos Kirk

Johnson The New York Times, April 22, 2006 pA1(L)

 Science Daily: Putting Coal Ash Back Into Mines A Viable Option For

Disposal, But Risks Must Be Addressed

 National Park Service: Mining Operations Management

 Arizona Mining Association: From the Ground Up: Mining/Mineral

Resource Development

Core Case Study: The Nanotechnology Revolution

 Nanotechnology uses science and engineering to create materials

out of atoms and molecules at the scale of less than 100

nanometers

• Does not use renewable resources.

• Can move through cell membranes:

Figure 15-1

GEOLOGIC PROCESSES

 The earth is made up of a core, mantle, and crust and is constantly

changing as a result of processes taking place on and below its surface

 The earth’s interior consists of:

molten outer core that is extremely hot.

 Mantle : solid rock with a rigid outer part

(asthenosphere) that is melted pliable rock.

 Crust : Outermost zone which underlies the

continents.

GEOLOGIC PROCESSES

 Major features of the earth’s crust and upper mantle

Figure 15-2

Fig 15-2, p 336

Volcanoes

Folded mountain belt

Abyssal floor

Oceanic ridge

Abyssal floor Trench

Abyssal hills

Craton Abyssal plain

Continental rise

Continental crust (lithosphere)

Mantle (lithosphere )

Mantle (lithosphere) Mantle (asthenosphere)

Oceanic crust Continental

Material cools

as it reaches the outer mantle

Cold dense material falls back through mantle Hot

material rising through the mantle

Mantle convection cell

Two plates move towards each other

One is subducted back into the mantle on a falling convection current.

Mantle

Hot outer core Inner

Ocea nic te

ctoni c plate

Oceanic tectonic

plate

Oceanic crust

GEOLOGIC PROCESSES

 Huge volumes of heated and molten rack moving around the earth’s

interior form massive solid plates that move extremely slowly across the earth’s surface

 Tectonic plates : huge rigid plates that are

moved with convection cells or currents by

The Earth’s Major Tectonic Plates

Figure 15-4

The Earth’s Major Tectonic Plates

 The extremely slow movements of these plates cause them to grind into one another at convergent plate boundaries, move apart at divergent plate boundaries and slide past at transform plate boundaries

Figure 15-4

Fig 15-4, p 338

Fig 15-4a, p 338

EURASIAN PLATE

NORTH AMERICAN PLATE

ANATOLIAN PLATE

JUAN DE

CARIBBEAN PLATE

PHILIPPINE PLATE

ARABIAN PLATE

AFRICAN PLATE PACIFIC

AMERICAN PLATE

NAZCA

INDIA-PLATE

SOMALIAN SUBPLATE

ANTARCTIC PLATE Divergent plate

Fig 15-4b, p 338

Trench Volcanic island arc Craton

Transform fault Lithosphere

Su bd

uc tio

n z on e

Divergent plate boundaries Convergent plate boundaries Transform faults

Rising magma

GEOLOGIC PROCESSES

 The San Andreas Fault is

an example of a transform fault

Figure 15-5

Wearing Down and Building Up the

Earth’s Surface

 Weathering is an external process that wears the earth’s

surface down

Figure 15-6

Physical weathering (wind, rain, thermal expansion and

contraction, water freezing)

Particles of parent material

MINERALS, ROCKS, AND THE

ROCK CYCLE

 The earth’s crust consists of solid inorganic elements and compounds called minerals that can sometimes be used as resources

 Mineral resource : is a concentration of

naturally occurring material in or on the earth’s crust that can be extracted and processed into useful materials at an affordable cost.

General Classification of Nonrenewable Mineral Resources

 The U.S Geological Survey classifies mineral resources into four major categories:

 Identified : known location, quantity, and quality

or existence known based on direct evidence and measurements.

 Undiscovered : potential supplies that are

General Classification of Nonrenewable Mineral Resources

 Examples are fossil fuels (coal, oil), metallic minerals (copper, iron), and

nonmetallic minerals (sand, gravel)

Figure 15-7

Rock Cycle

Figure 15-8

Fig 15-8, p 343

Erosion Transportation

Weathering Deposition

Igneous rock Granite, pumice,

Cooling Heat, pressure,

stress (molten rock) Magma

Melting

Metamorphic rock Slate, marble, gneiss, quartzite

ENVIRONMENTAL EFFECTS OF USING MINERAL RESOURCES

 The extraction, processing, and use of mineral resources has a large environmental impact

Figure 15-9

(scattered in environment) Recycling

Fig 15-10, p 344

Natural Capital Degradation

Extracting, Processing, and Using Nonrenewable Mineral and Energy Resources

accidents; health hazards, mine waste dumping, oil spills and blowouts; noise; ugliness; heat

safety and health hazards; ugliness; heat

of air, water, and soil;

solid and radioactive wastes; safety and health hazards; heat

ENVIRONMENTAL EFFECTS OF USING MINERAL RESOURCES

 Minerals are removed through a variety of methods that vary widely in their costs, safety factors, and levels of environmental harm

 A variety of methods are used based on mineral depth

 Surface mining : shallow deposits are removed.

 Subsurface mining : deep deposits are removed.

Open-pit Mining

 Machines dig holes and remove ores, sand, gravel, and stone

 Toxic groundwater can accumulate at the bottom

Figure 15-11

Area Strip Mining

 Earth movers strips away overburden, and giant shovels removes mineral deposit

 Often leaves highly erodible hills of rubble called spoil

Figure 15-12

Contour Strip Mining

 Used on hilly or mountainous terrain

 Unless the land is restored,

a wall of dirt is left in front of

a highly erodible bank called

Figure 15-13

Mountaintop Removal

 Machinery removes the tops

of mountains to expose coal

 The resulting waste rock and dirt are dumped into the

streams and valleys below

Figure 15-14

Mining Impacts

 Metal ores are smelted or treated with (potentially toxic) chemicals to extract the desired metal

Figure 15-15

SUPPLIES OF MINERAL

RESOURCES

 Depletion curves for a renewable resource using three sets of assumptions

lines represent times when 80%

depletion occurs.

Figure 15-16

increase reserves by improved mining technology, higher prices, and new discoveries

C

Present Depletion

time A

Depletion time B

Depletion time C Time

Getting More Minerals from the

Ocean

 Hydrothermal deposits form when mineral-rich superheated water shoots out of vents in solidified magma on the ocean floor

Figure 15-17

Fig 15-17, p 350

Black smoker

White smoker

Sulfide deposits

Magma White clam White

worms

USING MINERAL RESOURCES

Fig 15-18, p 351

Solutions Sustainable Use of Nonrenewable Minerals

• Do not waste mineral resources.

• Recycle and reuse 60–80% of mineral resources.

• Include the harmful environmental costs of

mining and processing minerals in the prices

of items (full-cost pricing).

• Reduce subsidies for mining mineral resources.

• Increase subsidies for recycling, reuse, and

finding less environmentally harmful substitutes.

• Redesign manufacturing processes to use less

mineral resources and to produce less pollution

and waste.

• Have the mineral-based wastes of one

manufacturing process become the raw

materials for other processes.

• Sell services instead of things.

• Slow population growth.

Case Study:

The Ecoindustrial Revolution

 Growing signs point to an ecoindustrial revolution taking place over the next 50 years

 The goal is to redesign industrial manufacturing processes to mimic how nature deals with wastes

exchange webs in which wastes from

manufacturer become raw materials for another.

Case Study:

The Ecoindustrial Revolution

Figure 15-19

al g as

Waste calcium sulfate

W as