Geology and Nonrenewable Minerals - PowerPoint PPT Presentation

Loading...

PPT – Geology and Nonrenewable Minerals PowerPoint presentation | free to download - id: 602706-OGU4N



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Geology and Nonrenewable Minerals

Description:

Title: PowerPoint Presentation Author: you Last modified by: Andrea Knowles Created Date: 6/12/2007 12:19:41 AM Document presentation format: On-screen Show (4:3) – PowerPoint PPT presentation

Number of Views:214
Avg rating:3.0/5.0
Slides: 56
Provided by: you9230
Learn more at: http://images.pcmac.org
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Geology and Nonrenewable Minerals


1
Geology and Nonrenewable Minerals
  • Chapter 15

2
Environmental Effects of Gold Mining
  • Gold producers
  • South Africa
  • Australia
  • United States
  • Canada
  • Cyanide heap leaching
  • Extremely toxic to birds and mammals
  • 2000 Collapse of a dam retaining a cyanide leach
    pond

Black Hills S. Dakota
3
Earths Major Geological Processes and Hazards
  • Gigantic plates in the earths crust move very
    slowly atop the planets mantle, and wind and
    water move the matter from place to place across
    the earths surface.
  • Natural geological hazards such as earthquakes,
    tsunamis, volcanoes, and landslides can cause
    considerable damage.

4
The Earth Is a Dynamic Planet
  • What is geology?
  • Three major concentric zones of the earth
  • Core solid inner part surrounded by a liquid
    core
  • Mantle mostly solid rock
  • Including the asthenosphere hot,partly melted
    rock that flows and can be deformed like plastic
  • Crust
  • Continental crust
  • Oceanic crust 71 of crust

5
Major Features of the Earths Crust and Upper
Mantle
6
The Earth beneath your feet is moving.
  • Convection cells, or currents move large
    volumes of rock and heat in loops within the
    mantle like gigantic conveyer belts
  • Tectonic Plates dozen or so huge rigid plates
    move extremely slowly atop the denser mantle on
    hot, soft rock in the underlying asthenosphere
  • Lithosphere continental and oceanic crust and
    the rigid, outermost part of the mantle

7
The Earths Crust Is Made Up of a Mosaic of Huge
Rigid Plates Tectonic Plates
8
The Earths Major Tectonic Plates
EURASIAN PLATE
NORTH AMERICAN PLATE
ANATOLIAN PLATE
JUAN DE FUCA PLATE
CHINA SUBPLATE
CARIBBEAN PLATE
PHILIPPINE PLATE
ARABIAN PLATE
AFRICAN PLATE
INDIA PLATE
PACIFIC PLATE
PACIFIC PLATE
COCOS PLATE
SOUTH AMERICAN PLATE
NAZCA PLATE
AUSTRALIAN PLATE
SOMALIAN SUBPLATE
SCOTIA PLATE
ANTARCTIC PLATE
Divergent plate boundaries
Transform faults
Convergent plate boundaries
Fig. 14-4, p. 347
9
The Earth beneath your feet is moving .
  • Three types of boundaries between plates
  • Divergent plates plates move apart
  • Magma flows up through the resulting cracks
  • Oceanic ridge some of which have higher peaks
    and deeper canyons than earths continents
  • Convergent plates oceanic plate collides with a
    continental plate,
  • Subduction the latter rides up over the
    denser oceanic plate and pushes it down into the
    mantle
  • Subduction zone area where collision and
    subduction takes place
  • Trench forms at the boundary between the 2
    converging plates
  • Transform fault e.g. San Andreas fault where
    plates slide and grind past one another along a
    fracture. Most located on the ocean floor

10
The San Andreas Fault as It Crosses Part of the
Carrizo Plain in California, U.S.
11
Some Parts of the Earths Surface Build Up and
Some Wear Down
  • Internal geologic processes
  • Generated by heat from the earths interior
    ,generally build up the earths surface in the
    form of continental and oceanic crust including
    mountains and volcanoes
  • External geologic processes
  • Weathering driven directly or indirectly by
    energy from the sun(mostly in the form of flowing
    water and wind)
  • Physical, Chemical, and Biological soil
  • Erosion
  • Wind
  • Flowing water
  • Human activities
  • Glaciers

12
Weathering Biological, Chemical, and Physical
Processes
13
Volcanoes Release Molten Rock from the Earths
Interior
  • Volcano magma reaches the earths surface
    through a..
  • Fissure central vent or a long crack
  • Magma
  • Lava magma that reaches the earths surface.
    Debris ranging from large chunks of larva rock to
    glowing hot ash, liquid lava and gases such as
    water vapor, carbon dioxide and sulfur dioxide .
    Much of the worlds volcanic activity is
    concentrated along the boundaries of the earths
    tectonic plates
  • 1980 Eruption of Mount St. Helens
  • 1991 Eruption of Mount Pinatubo cooled the
    earth average temperature for 15 months
  • Benefits of volcanic activity highly fertile
    soil, creates outstanding landforms (Crater Lake
    in Oregon)

14
Creation of a Volcano
15
Earthquakes Are Geological Rock-and-Roll Events
Richter scale Insignificant lt4.0 Minor
4.04.9 Damaging 5.05.9 Destructive
6.06.9 Major 7.07.9 Great gt8.0
Earthquake Seismic waves Focus Epicenter Magnitud
e Amplitude
Foreshocks and aftershocks Primary effects of
earthquakes shaking, permanent vertical or
horizontal displacement of the ground
16
Major Features and Effects of an Earthquake
17
Areas of Greatest Earthquake Risk in the United
States
18
Areas of Greatest Earthquake Risk in the World
19
Earthquakes on the Ocean Floor Can Cause Huge
Waves Called Tsunamis
  • Tsunami, tidal wave generated when part of the
    ocean floor suddenly rises or drops. Usually
    occurs offshore in subduction zones.
  • Detection of tsunamis by ocean buoys, pressure
    recorders on the ocean floor which measures
    changes in water pressure as the waves pass over
    it data relayed via satellites tsunami warning
    systems
  • December 2004 Indian Ocean tsunami
  • Magnitude of 9.15
  • Role of coral reefs and mangrove forests in
    reducing death toll

20
Formation of a Tsunami and Map of Affected Area
of Dec 2004 Tsunami
21
Shore near Banda Aceh,Gleebruk in Indonesia
before and after tsunami
After December 28, 2004
Before June 23, 2004
22
Gravity and Earthquakes Can Cause Landslides
  • Mass wasting detached or loose rock, soil and
    mud to slide down steep slopes near the shores of
    oceans or lakes
  • Slow movement
  • Fast movement
  • Rockslides
  • Avalanches
  • Mudslides 1970 Peru, buried the town of
    Yungay and killed 17,000 people
  • Effect of human activities on such geological
    events
  • forest clearing, road building , crop growing,
    building houses

23
Earths Rocks are Recycled..
  • The three major types of rocks found in the
    earths crustsedimentary, igneous, and
    metamorphicare recycled very slowly by the
    process of erosion, melting, and metamorphism.

24
There Are Three Major Types of Rocks
  • Earths crust
  • Composed of minerals and rocks
  • Three broad classes of rocks, based on formation
  • Sedimentary Igneous
  • Sandstone Granite
  • Shale Lava rock
  • Dolomite Metamorphic
  • Slate Anthracite
  • Lignite Slate
  • Bituminous coal Marble

25
The Earths Rocks Are Recycled Very Slowly
  • Rock cycle the interaction of physical and
    chemical processes that change rocks from one
    type to another. Slowest of the earths cyclic
    processes

26
What Are Mineral Resources, and what are their
environmental effects?
  • Some naturally occurring materials in the earths
    crust can be extracted and made into useful
    products in processes that provide economic
    benefits and jobs.
  • 100 minerals naturally occurring material
  • fossil fuels(coal)
  • metallic(aluminum, iron, copper)
  • non-metallic(sand, gravel,limestone)
  • Ore large concentration of a particular mineral,
    often a metal
  • High-grade ore large amount of desired
    non-renewable resource
  • Low-grade ore small amount of the resource

27
Mineral Use Has Advantages and Disadvantages
  • Mine and convert minerals into useful products
  • Disadvantages enormous amounts of energy,
    disturbs land, erode soil, produce solid waste,
    air and water pollution

Life cycle of a metal resource
28
Extracting, Processing, Using Nonrenewable
Mineral and Energy Resources
29
There Are Several Ways to Remove Mineral
Deposits
  • Surface mining shallow deposits removed
  • mechanized equipment strips away overburden(soil
    and rock overlay), discarded as waste called
  • Used to extract 90 of the nonfuel mineral and
    rock resources and 6- of the coal
  • Type of surface mining used depends on
  • Resource
  • Local topography
  • Subsurface mining
  • Deep deposits removed
  • Used to extract coal and metal ores

30
Types of Surface Mining
  • Open Pit Mining machines dig hole and remove
    ore
  • Strip Mining earth movers strip overburden and
    power shovels remove deposit
  • Contour Mining mine coal on hilly terrain. Wall
    of dirt left in front of a highly erodible bank
    of soil and rock called highwall
  • Mountain Top Removal Appalachian Mountains ,
    draglines, explosives remove top of mountain to
    expose seams

31
Open-Pit Mine in Western Australia
32
Undisturbed land
Overburden
Highwall
Coal seam
Overburden
Pit
Bench
Coal seam
Contour Strip Mining in hilly areas
Spoil banks
Fig. 14-17, p. 357
33
Mountaintop Coal Mining in West Virginia, U.S.
34
Mining has harmful effects.
  • Scarring and disruption of the land surface
  • E.g., spoils banks
  • Loss of rivers and streams 1900 km have been
    buried
  • Subsidence collapse of land

35
Mining Has Harmful Environmental Effects
  • Major pollution of water and air toxin-laced
    mining waste deposited in areas other than mining
    site . Acid Mine Drainage
  • Effect on aquatic life ph change,40 of all US
    watersheds contaminated
  • Large amounts of solid waste
  • 3/4th of all US solid waste
  • mining gold

Illegal Gold Mine
36
Removing Metals from Ores Has Harmful
Environmental Effects
  • Ore extracted by mining
  • Ore mineral desired metal
  • Gangue waste material. Removing the gangue from
    the ores produces tailings, Particles of toxic
    metals blown by the wind or leached by rainfall
    can contaminate surface water and groundwater.
  • Smelting heating ores to release metals.
  • Without proper equipment, releases sulfur dioxide
    and suspended particles, damage vegetation and
    acidify soils
  • Water pollution highly toxic cyanide salts to
    extract gold from its ore. Leave behind cyanide
    laden water
  • Summitville Gold Mining, Co

37
Summitville Gold Mining Site in Colorado, U.S.
38
Ecological Restoration of a Mining Site in New
Jersey, U.S.
39
How Long Will Supplies of Nonrenewable Mineral
Resources Last?
  • All nonrenewable mineral resources exist in
    finite amounts, and as we get closer to depleting
    any mineral resource, the environmental impacts
    of extracting it generally become more harmful.
  • Relatively abundant deposits of iron and aluminum
    (bauxite)
  • Scarce manganese,chromium,cobalt,platinum
  • An increase in the price of a scarce mineral
    resource can lead to increased supplies and more
    efficient use of the mineral, but there are
    limits to this effect.

40
Uneven distribution of minerals
  • Most of the nonrenewable mineral resources
    supplied by
  • Canada
  • United States
  • Germany
  • Russia
  • South Africa self sufficient in all key
    minerals, largest producer of gold, chromium and
    platinum
  • Australia

8 of world population, consume 75 of the
worlds key metals China increasing consumption
41
Four Strategic metal resources.
  • Manganese
  • Cobalt
  • Chromium
  • Platinum
  • US has little or no reserves of these metals
    which are essential for the countrys economy and
    military strength
  • May ave to switch to nano materials

42
The Nanotechnology Revolution
  • Nanotechnology, tiny tech use carbon, oxygen
    and silicone atoms to create everything from
    medicines,solar cells to automobile bodies
  • Currently used in more than 400 items odor
    eating socks, wrinkle free clothes, cosmetics,
    sun screens
  • Nanoparticles
  • Are they safe?
  • Investigate potential ecological, economic,
    health, and societal risks
  • Develop guidelines for their use until more is
    known about them

43
Economic Depletion of non renewable mineral
resources
  • Future supply depends on
  • Actual or potential supply of the mineral
  • Rate at which it is used
  • When it becomes economically depleted
  • Recycle or reuse existing supplies
  • Waste less
  • Use less
  • Find a substitute
  • Do without

44
Depletion Curves for a Nonrenewable Resource
Depletion time time it takes to use up
approximately 80 of the reserves of a mineral at
a given rate of use
45
Market Prices Affect Supplies of Nonrenewable
Minerals
  • Subsidies and tax breaks to mining companies keep
    mineral prices artificially low
  • Does this promote economic growth and national
    security?
  • Scarce investment capital hinders the development
    of new supplies of mineral resources

46
The U.S. General Mining Law of 1872
  • Encouraged mineral exploration and mining of
    hard-rock minerals on U.S. public lands
  • Developed to encourage settling the West (1800s)
  • Until 1995, land could be bought for 1872 prices
  • Companies must pay for clean-up now

47
Is Mining Lower-Grade Ores the answer?
  • Factors limit the mining of lower grade ores
  • increased cost of mining
  • limited availability of fresh water , specially
    in arid areas
  • environmental impacts of increased land
    disruption, waste material and pollution produced
    during mining and processing
  • Use microorganisms that can extract minerals
    in-place or in-situmining.
  • Biomining genetic engineering techniques used
    to produce bacteria that can be used to extract a
    particular metal without disturbing the
    surrounding environment

48
Extend Supplies by Getting More Minerals from
the Ocean
  • Mineral resources dissolved in the ocean-very low
    concentrations, requires more energy and money
    than they are worth
  • Only magnesium, bromine and sodium chloride are
    abundant enough to be extracted profitably
  • Deposits of minerals in sediments along the
    shallow continental shelf and near shorelines
    sand, gravel,phosphates,sulfur,tin.copper,iron,tun
    gsten,silver,titanium,platinum,diamonds

49
Extend Supplies by Getting More Minerals from the
Ocean
  • Hydrothermal ore deposits sulfides, zinc,
    silver, copper precipitate out and build up as
    mineral deposits
  • currently costs too much to extract,
  • disputes over ownership
  • Metals from the ocean floor potato sized
    manganese nodules, that cover 25-50 of the
    Pacific ocean floor
  • Effect of mining on aquatic life
  • Environmental impact sea bed mining ,less
    impact than land (??)

50
How Can We Use Mineral Resources More
Sustainability?
  • Find substitutes for some scarce mineral
    resources
  • materials revolution silicon, ceramics,
    plastics
  • houses made of styroform sprayed with ceramic
    spray called Grancrete, reduces use of timber
  • high strength plastics and composite materials
    strengthened by light weight carbon and glass
    fibers are transforming the automobile and
    aerospace industries
  • making plastics requires fossil fuels and oil
  • Substitution may not always be possible
  • platinum, industrial catalyst
  • chromium stainless steel

51
We Can Recycle and Reuse Valuable Metals
  • Recycling
  • Lower environmental impact than mining and
    processing metals from ores
  • Reuse gold, silver, iron, copper, steel,
    aluminum, platinum
  • Recycling aluminum beverage cans and scrap
    aluminum produces 95 less air pollution, 97
    less water pollution and uses 95 less energy

52
There Are Many Ways to Use Mineral Resources More
Sustainability
  • How can we decrease our use and waste of mineral
    resources?
  • Pollution and waste prevention programs
  • 3M Pollution Prevention Pays (3P)
  • Cleaner production air pollution 70 lower,
    saved 750 million in waste disposal and material
    costs

53
Sustainable Use of Nonrenewable Minerals
54
Industrial Ecosystems Copying Nature
  • Mimic nature recycle and reuse most minerals and
    chemicals waste outputs of one organism becomes
    the nutrient inputs of another
  • Resource exchange webs wastes of one
    manufacturer becomes the raw materials for
    another
  • Ecoindustrial parks on brownfields, which are
    abandoned industrial sites
  • Industrial forms of biomimicry
  • Benefits come up with new environmentally
    beneficial and less resource-intensive chemicals
  • Better image among consumers

55
An Industrial Ecosystem in Denmark Mimics Natural
Food Web
About PowerShow.com