1. Geology and Nonrenewable Minerals
Chapter 14
PART 1

2. 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.

3. 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

4. 14-1 What Are the Earth’s Major Geological Processes and Hazards?
Concept 14-1A Gigantic plates in the earth’s crust move very slowly atop the planet’s mantle, and wind and water move the matter from place to place across the earth’s surface.
Concept 14-1B Natural geological hazards such as earthquakes, tsunamis, volcanoes, and landslides can cause considerable damage.

5. The Earth Is a Dynamic Planet
The earth’s 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

6. The Earth Beneath Your Feet is Moving
Plate Tectonics
The theory that Earth’s 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

7. The Earth’s Major Tectonic Plates

8. Major Features of the Earth’s Crust and Upper Mantle

9. Tectonic Plate Boundaries
Plates move apart at divergent plate boundaries.
Mid-ocean ridge – the site of sea-floor spreading

10. Tectonic Plate Boundaries
Plates grind into one another at convergent plate boundaries.
Folded mountains
Volcanic mountains

11. Tectonic Plate Boundaries
Plates slide past one another at transform plate boundaries.

12. Some Parts of the Earth’s Surface Build Up and Some Wear Down
Internal geologic processes
Generally build up the earth’s surface
Result from the heat generated by the Earth’s interior
External geologic processes
Wear down the Earth’s 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

13. Volcanoes Release Molten Rock from the Earth’s Interior
Volcanoes are simply vents in the earth's surface through which lava and other volcanic products erupt.

14. 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

15. 14-2 How Are the Earth’s Rocks Recycled?
Concept The three major types of rocks found in the earth’s crust—sedimentary, igneous, and metamorphic—are recycled very slowly by the process of erosion, melting, and metamorphism.

16. There Are Three Major Types of Rocks
A very slow geochemical cycle involves three types of rock found in the earth’s 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

17. Natural Capital: The Rock Cycle Is the Slowest of the Earth’s Cyclic Processes

18. 14-3 What Are Mineral Resources, and what are their Environmental Effects?
Concept 14-3A Some naturally occurring materials in the earth’s 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.

19. 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 earth’s crust vary in their abundance and distribution.
High Grade Ore – high percentage of desired mineral
Low Grade Ore – low percentage of desired mineral

20. 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.

21. Concentration of Minerals in Earth’s 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 %
Nickel %
Zinc %
Copper %
Lead %
Uranium %
Silver %
Gold %

22. 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

23. 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.

24. Extracting, Processing, Using Nonrenewable Mineral and Energy Resources