Geology and Nonrenewable Minerals

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Geology and Nonrenewable Minerals

• Chapter 14

PART 1
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GEOLOGIC TIMESCALE

• Geologists have divided Earth's history into a
  series of time intervals.
• The geologic time scale was constructed to
  visually show the duration of each time unit.

• The Earth is 4.6 billion years old.
• The geologic processes have been happening for a
  very long time.
• Humans just showed up at the end.

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GEOLOGIC TIMESCALE

• The time intervals are variable in length. This
  is because geologic time is divided using
  significant events in the history of the Earth.
• New biological developments
• Mass extinctions

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14-1 What Are the Earths Major Geological
Processes and Hazards?

• Concept 14-1A 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.
• Concept 14-1B Natural geological hazards such as
  earthquakes, tsunamis, volcanoes, and landslides
  can cause considerable damage.

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The Earth Is a Dynamic Planet

• The earths interior consists of
• Core innermost zone with solid inner core and
  molten outer core that is extremely hot
• Mantle liquid rock with a rigid outer part
  (asthenosphere) that is melted pliable rock
• Crust layer of solid rock (lithosphere) which
  underlies the continents and the oceans
• Continental crust
• Oceanic crust

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The Earth Beneath Your Feet is Moving

• Plate Tectonics
• The theory that Earths crust is divided into
  huge tectonic plates that float on magma or
  molten rock.
• Convection currents within the mantle move the
  plates around.
• Evidence
• Puzzle-like fit of the continents
• Matching plant/animal fossils on
  opposite sides of oceans
• Matching rock layers on opposite
  sides of oceans
• Evidence of past climates

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The Earths Major Tectonic Plates
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Major Features of the Earths Crust and Upper
Mantle

• Major features of the earths crust and upper
  mantle.

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Tectonic Plate Boundaries

• Plates move apart at divergent plate boundaries.

• Mid-ocean ridge the site of sea-floor spreading

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Tectonic Plate Boundaries

• Plates grind into one another at convergent plate
  boundaries.
• Folded mountains
• Volcanic mountains

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Tectonic Plate Boundaries

• Plates slide past one another at transform plate
  boundaries.

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Some Parts of the Earths Surface Build Up and
Some Wear Down

• Internal geologic processes
• Generally build up the earths surface
• Result from the heat generated by the Earths
  interior
• External geologic processes
• Wear down the Earths surface and move it around
• Result from solar energy and gravity (wind,
  flowing water)

• Weathering Processes that break rocks down into
  smaller pieces
• Plays key role in soil formation
• Different kinds of rock will result in different
  soil properties

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Volcanoes Release Molten Rock from the Earths
Interior

• Volcanoes are simply vents in the earth's surface
  through which lava and other volcanic products
  erupt.

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Earthquakes Are Geological Rock-and-Roll Events

• The sudden release of energy stored up by the
  movement of tectonic plates

• Energy travels as seismic waves, each with own
  type of movement and speed.
• P-wave
• S-wave
• Surface
• waves

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14-2 How Are the Earths Rocks Recycled?

• Concept 14-2 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.

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There Are Three Major Types of Rocks

• A very slow geochemical cycle involves three
  types of rock found in the earths crust
• Igneous rock (granite, pumice, basalt)
• Solidified lava or magma
• Sedimentary rock (sandstone, limestone, shale)
• Fusion of eroded sediments
• Metamorphic rock (slate, marble, quartzite)
• Application of heat / pressure

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Natural Capital The Rock Cycle Is the Slowest of
the Earths Cyclic Processes
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14-3 What Are Mineral Resources, and what are
their Environmental Effects?

• Concept 14-3A Some naturally occurring materials
  in the earths crust can be extracted and made
  into useful products in processes that provide
  economic benefits and jobs.
• Concept 14-3B Extracting and using mineral
  resources can disturb the land, erode soils,
  produce large amounts of solid waste, and pollute
  the air, water, and soil.

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We Use a Variety of Nonrenewable Mineral
Resources

• Mineral naturally occurring, inorganic, solid
  element or compound with a definite chemical
  composition and a regular internal crystal
  structure.
• Mineral resource (Ore) a deposit of minerals
  that can be extracted and processed into useful
  materials at an affordable cost.
• Deposits of nonrenewable mineral resources in the
  earths crust vary in their abundance and
  distribution.
• High Grade Ore high percentage of desired
  mineral
• Low Grade Ore low percentage of desired mineral

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We Use a Variety of Nonrenewable Mineral
Resources

• Examples of nonrenewable metal and nonmetal
  mineral resources
• Aluminum beverage cans, motor vehicles,
  aircraft
• Steel (alloy of iron and other elements)
  buildings
• Copper electrical and communications wiring
• Platinum electrical equipment, industrial
  catalyst
• Gold electrical equipment, jewelry, medical
  implants
• Sand glass, bricks, concrete
• Limestone, - road rock, concrete, cement
• Manganese, Cobalt, Chromium light bulbs,
  computers, automobiles, aircraft, etc.

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Concentration of Minerals in Earths Crust
Aluminum 8 Iron 5.8 most Fe
and Al is in silicate minerals (like sand) and
is, therefore, not used as an
ore Titanium 0.82 Nickel 0.0075 Zinc
0.0082 Copper 0.0058 Lead
0.0013 Uranium 0.00016 Silver
0.000008 Gold 0.0000004
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Classification of Nonrenewable Mineral Resources

• The U.S. Geological Survey classifies mineral
  resources into four major categories
• Identified location, quantity, and quality or
  existence known based on direct evidence and
  measurements.
• Undiscovered potential supplies that are assumed
  to exist.
• Reserves identified resources that can be
  extracted profitably.
• Other undiscovered or identified resources not
  classified as reserves

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The Life Cycle of a Metal Resource

• The extraction, processing, and use of mineral
  resources has a large environmental impact.
• Mining of low grade ore requires more energy,
  water, and produces more waste.

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Extracting, Processing, Using Nonrenewable
Mineral and Energy Resources