1. Geology and Nonrenewable Minerals chapter 14

2. Core Case Study: Environmental Effects of Gold Mining
Gold producers
South Africa
Australia
United States
Canada
Cyanide heap leaching- controversial
Extremely toxic to birds and mammals
Ponds can leak or overflow
2000: Collapse of a dam retaining a cyanide leach pond
Impact on organisms and the environment

3. Gold Mine with Cyanide Leach Piles and Ponds in South Dakota, U.S.

4. GOLD IN GEORGIA Has been found in 37 counties
The gold rush started near Dahlonega. By 1940, gold was harder to find and many miners left for California

5. 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.

6. The Earth Is a Dynamic Planet
What is geology? (dynamic processes that occur on the Earth’s surface and in its interior)
Three major concentric zones of the earth
Core – solid inner core and liquid outer core
Mantle
Including the asthenosphere – partly melted rock that flows
Crust
Continental crust
Oceanic crust: 71% of crust

8. Planet Earth: Lithosphere
Lithosphere - Earth’s crust and upper mantle
Thickness varies from 10 to 200 km
1. Oceanic crust – floor of deep ocean basins
Composed of basalt (igneous). Also iron, magnesium and calcium.
Thin (4-5 km) and young.
2. Continental crust -- forms continents.
Composed of granite (igneous). Also silicon, aluminum, sodium and potassium.
Thickness 35 to 70 km.
Old crust.

9. The Lithosphere
The crust and the upper layer of the mantle together make up a zone of rigid, brittle rock called the Lithosphere.

10. The Crust
The crust is composed of two rocks. The continental crust is mostly granite. The oceanic crust is basalt. Basalt is much denser than the granite. Because of this, the less dense continents ride on the denser oceanic plates.

11. The Mantle
The Mantle is the largest layer of the Earth. The middle mantle is composed of very hot dense rock that flows like asphalt under a heavy weight. The movement of the middle mantle (asthenosphere) is the reason that the crustal plates of the Earth move.

12. Convection Currents
The middle mantle "flows" because of convection currents. Convection currents are caused by the very hot material at the deepest part of the mantle rising, then cooling and sinking again --repeating this cycle over and over.

13. Convection Currents
The next time you heat anything like soup or water in a pan you can watch the convection currents move in the liquid. When the convection currents flow in the asthenosphere they also move the crust. The crust gets a free ride with these currents, like the cork in this illustration.

14. The Outer Core
The core of the Earth is like a ball of very hot metals. The outer core is so hot that the metals in it are all in the liquid state. The outer core is composed of the melted metals of nickel and iron.

15. The Inner Core
The inner core of the Earth has temperatures and pressures so great that the metals are squeezed together and are not able to move about like a liquid, but are forced to vibrate in place like a solid. (Ni, Fe, Au, Pt and U)

16. Let’s Review! What are the 3 concentric zones of the earth?
CRUST, MANTLE AND CORE
What is the main rock that comprises the continental crust?
GRANITE
What is the main rock that comprises the oceanic crust?
BASALT

17. The crust and upper mantle make up the _____.
LITHOSPHERE
What makes the crustal plates move?
CONVECTION CURRENTS
The layer of the mantle that flows and is responsible for these convection currents is the _____.
ASTHENOSPHERE

18. Mantle (asthenosphere)
Volcanoes
Folded mountain belt
Abyssal floor
Oceanic ridge
Abyssal floor
Abyssal hills
Trench
Craton
Abyssal plain
Oceanic crust (lithosphere)
Abyssal plain
Continental shelf
Continental slope
Continental rise
Mantle (lithosphere)
Continental crust (lithosphere)
Mantle (lithosphere)
Figure 14.2
Major features of the earth’s crust and upper mantle. The lithosphere, composed of the crust and outermost mantle, is rigid and brittle. The asthenosphere, a zone in the mantle, can be deformed by heat and pressure.
Mantle (asthenosphere)
Fig. 14-2, p. 346

19. The Earth Beneath Your Feet Is Moving (2)
Three types of boundaries between plates
Divergent plates
Oceanic ridge and continental rift valleys
EX: Mid-Atlantic Ridge, East Pacific Rise, East African Great Rift Valley
Convergent plates
Subduction, subduction zone
Trench
EX: Cascade Mt Range (Ca to Wa- Mt. St. Helens)
Transform faults
Sliding of plates past each other
EX: San Andreas Fault

20. Collision between two continents
Spreading center
Ocean trench
Oceanic tectonic plate
Oceanic tectonic plate
Plate movement
Collision between two continents
Plate movement
Tectonic plate
Subduction zone
Oceanic crust
Oceanic crust
Continental crust
Continental crust
Cold dense material falls back through mantle
Material cools as it reaches the outer mantle
Mantle convection cell
Hot material rising through the mantle
Figure 14.3
The earth’s crust is made up of a mosaic of huge rigid plates, called tectonic plates, which move very slowly across the asthenosphere in response to forces in the mantle. See an animation based on this figure at CengageNOW™.
Two plates move towards each other. One is subducted back into the mantle on a falling convection current.
Mantle
Hot outer core
Inner core
Fig. 14-3, p. 346

21. m 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
Figure 14.4
The earth’s major tectonic plates. See an animation based on this figure at CengageNOW. Question: What plate are you riding on?
SCOTIA PLATE
ANTARCTIC PLATE
Divergent plate boundaries
Convergent plate boundaries
Transform faults
Fig. 14-4, p. 347

22. PLATES Move at about the rate a fingernail grows
Mountains, earthquakes and volcanoes occur at plate boundaries
Divergent- ridges in ocean/rifts on land
Convergent- subduction/trenches in oceans and mountains (orogonic belt) on land
Transform fault- 2 plates slide past one another (San Andreas Fault)

23. The San Andreas Fault as It Crosses Part of the Carrizo Plain in California, U.S.

24. Mount Everest Base Camp Himalayas Khumbu Icefall

25. Mount Everest
Mt Everest- tallest mountain on land (29,029 ft = 8848 m) (4-10 cm) inches higher every year
Everest is part of the Himalaya mountain range along the border of Nepal and Tibet.
At 9,800 feet, for example, there's about 2/3 of the oxygen in the air than at sea level. At 20,000 ft, there is roughly half the oxygen content in the air. At 29,035ft, the summit of Everest, there is only a third of the oxygen in the air.

26. At the summit, the temperature can be 100°F below zero
At the summit, the temperature can be 100°F below zero. But on a good summit day, a climber can expect around -15°F
On May 29, 1953, Tenzing
Norgay Sherpa of Nepal &
Edmund Percival Hillary of
New Zealand climbed to
the summit of Everest via
the Southeast Ridge Route

27. Divergent boundaries Africa’s Great Rift Valley
The oceanic ridge is a continuous submarine mountain chain extending approximately 80,000 km (50,000 miles) through all the world’s oceans

28. Some Parts of the Earth’s Surface Build Up and Some Wear Down
Internal geologic processes
Generally build up the earth’s surface
External geologic processes (driven by the sun and influenced by gravity)
Weathering (key in soil formation)
Physical, Chemical, and Biological processes that break down rock
Erosion
Wind
Flowing water
Human activities
Glaciers- (formed the Great Lakes)

29. Parent material (rock)
Biological weathering
(tree roots and lichens)
Chemical weathering (water, acids, and gases)
Physical weathering
(wind, rain, thermal expansion and contraction, water freezing)
Figure 14.6
Weathering: Biological, chemical, and physical processes weather or convert rock into smaller fragments and particles. It is the first step in soil formation.
Particles of parent material
Fig. 14-6, p. 348

30. Volcanoes Release Molten Rock from the Earth’s Interior
Fissure- vent or crack
Magma
Lava
1980: Eruption of Mount St. Helens (Mount Pinatubo)
1991: Eruption of Mount Pinatubo- Philippines
Benefits of volcanic activity- forms mountains, lakes (Crater Lake, OR), fertile soils

31. Partially molten asthenosphere
Extinct volcanoes
Eruption cloud
Ash
Acid rain
Ash flow
Lava flow
Mud flow
Central vent
Landslide
Magma conduit
Magma reservoir
Figure 14.7
A volcano is created when magma in the partially molten asthenosphere rises in a plume through the lithosphere to erupt on the surface as lava, which builds a cone. Sometimes, internal pressure is high enough to cause lava, ash, and gases to be ejected into the atmosphere or to flow over land, causing considerable damage (Concept 14-1B). Chains of islands have been created by volcanoes that erupted and then became inactive.
Solid lithosphere
Upwelling magma
Partially molten asthenosphere
Fig. 14-7, p. 349

32. Earthquakes Are Geological Rock-and-Roll Events (1)
Seismic waves- vibrations caused by earthquakes
Focus
Epicenter
Magnitude – amount of energy released
Amplitude – size of seismic waves

33. Earthquakes Are Geological Rock-and-Roll Events (2)
Richter scale – a logarithmic scale recorded by a seismograph. Measures the amplitudes of the waves produced. An earthquake of magnitude 5 has 10X more ground shaking than a magnitude of 4. It is the energy though that knocks down buildings and causes damage. A magnitude of 5 releases 32X more energy than a magnitude 4 eq.
Insignificant: <4.0
Minor: 4.0–4.9
Damaging: 5.0–5.9
Destructive: 6.0–6.9
Major: 7.0–7.9
Great: >8.0

34. Earthquakes Are Geological Rock-and-Roll Events (3)
Foreshocks and aftershocks
Primary effects of earthquakes
Due to the shaking and the resulting damage to buildings/infrastructure and due to loss of life or injury, land displacement
Secondary effects
Rock slides, flooding, liquefaction of sediments, fires, and tsunamis
Reduce damage by mapping faults, strengthening building codes, preparing emergency teams, storing supplies and educating the public

35. Liquefaction of recent sediments causes buildings to sink
Two adjoining plates move laterally along the fault line
Earth movements cause flooding in low-lying areas
Landslides may occur on hilly ground
Figure 14.8
Major features and effects of an earthquake, one of nature’s most powerful events.
Shock waves
Focus
Epicenter
Fig. 14-8, p. 350

36. Areas of Greatest Earthquake Risk in the United States

37. Areas of Greatest Earthquake Risk in the World

38. EQ TRIVIA! There are over 1 million eq a year
There are over 10,000 eq in California a year.
San Andreas Fault is over 800 miles long.

39. Earthquakes on the Ocean Floor Can Cause Huge Waves Called Tsunamis
Tsunami, tidal wave
Can travel as fast as a jet plane
Detection of tsunamis
buoys, pressure recorder
December 26, 2004: Indian Ocean tsunami
Magnitude of 9.15 earthquake
Waves as high as 100 feet, 228,000 were killed
Coral reefs and mangrove forests reduce wave impact. (mangrove forests had been cleared and many reefs have been damaged in last 30 years)

40. Shore near Gleebruk in Indonesia before and after the Tsunami on June 23, 2004

42. Undersea thrust fault Upward wave Bangladesh India Burma Thailand
Earthquake in seafloor swiftly pushes water upwards, and starts a series of waves
Waves move rapidly in deep ocean reaching speeds of up to 890 kilometers per hour.
As the waves near land they slow to about 45 kilometers per hour but are squeezed upwards and increased in height.
Waves head inland causing damage in their path.
Undersea thrust fault
Upward wave
Bangladesh
India
Burma
Thailand
Figure 14.11
Formation of a tsunami and map of area affected by a large tsunami in December 2004.
Malaysia
Sri Lanka
Earthquake
Indonesia
Sumatra
December 26, 2004, tsunami
Fig , p. 352

43. Gravity and Earthquakes Can Cause Landslides
Mass wasting
Slow movement or
Fast movement
Rockslides
Avalanches
Mudslides
1970, earthquake in Peru caused massive landslide that killed 17,000 people
Effect of human activities such as forest clearing, road building and crop growing increases the frequency of and damage caused

44. What do you remember??
What mountains were formed at a convergent boundary?
CASCADES AND HIMALAYAS
How were the Hawaiian Islands formed
BY A HOT SPOT
Name a feature at a divergent boundary
AFRICAN RIFT VALLEY, OCEANIC RIDGE
Name a famous transform fault
SAN ANDREAS FAULT

45. How are earthquakes recorded?
RICHTER SCALE
What is the tallest mountain on land?
MOUNT EVEREST
Name 3 factors of erosion
WIND, WATER, GLACIERS AND HUMAN ACTIVITIES

46. Study the following website
Study the following website. For site #3, take the quiz, save it as a word document, and send it to me through edmodo.
(hotspots)

47. 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.