1. Chapter 8: Earth Systems

2. Hybrid Electric Vehicles
Reduce fossil fuel use.
Use scarce metals: lithium, neodymium and lanthalmum.
Cars may be limited by these needed materials.
Both extraction procedures are types of surface mining, which can have severe environmental impacts.

5. The Availability of Earth’s Resources Was Determined When the Planet Formed
The uneven geographic distribution has driven many economic and political conflicts.
Core: 3000km down! Made up of nickel and some iron.
Mantle: molten rock (magma).

6. Asthenosphere: outer part of the mantle, consists of semi-molten, ductile (flexible) rock.
Lithosphere: the brittle most outer part (60 miles thick). Made up of plates.

10. Earth is Dynamic and Constantly Changing
Geological Cycle Consists of 3 Processes
Tectonic Cycle
Rock Cycle
Soil Formation

14. Convection and Hot Spots
Earth remains very hot at the center as a result of radioactive decay.
Plumes of magma that well upwards are called hot spots.
Plate Tectonics: the Earth’s lithosphere is divided into plates, most of which are in constant motion.
Oceanic plates sink due to the high content of iron while the continental plates are less dense therefore rise above the oceanic plates.

15. Sea Floor Spreading: As oceanic plates move apart rising magma forms new oceanic crust on the seafloor at the boundaries of those plates.
Where oceanic plates meet continental plates, old oceanic crust is pulled downward, beneath the continental lithosphere, and the heavier oceanic crust slides underneath the lighter continental plate.
This is called subduction.

16. Volcanoes: when a plate moves over a hot spot and the heat form the rising mantle plume will melt the crust.

19. Types of Plate Contact
Divergent Plate Boundaries: plates move away from each other (seafloor spreading) and creates new lithosphere.

21. Convergent Plate Boundaries: plates move toward one another and collide. Forms long, narrow coastal ranges such as the Andes.
Melted subducted plate may be the source of a new volcano.
If two continental plates meet, both plate margins may be lifted, forming mid-continental mountain ranges.

25. Transform Fault Boundary: When plates slide past one another.
Moves about 1.4 inches per year.

27. Faults and Earthquakes
Fault: fracture in rock across where there is movement.
Fault Zone: large expansion of rock movement where the plates meet. Areas of seismic activity.
Earthquake: rocks of the lithosphere rupture unexpectedly along the fault.
Epicenter: exact point on the surface of the Earth directly where the rock ruptures.

29. Richter Scale: measure of the largest ground movement that occurs during an earthquake.
Richter scale is logarithmic, increasing by a factor of 10 for each unit increase.
2008 a 7.9 earthquake hit in China killing 69,000
2010 a 7.0 hit in Haiti killing 200,000
Nuclear power plants are at significant risk.

33. Rock Cycle Recycles Scarce Minerals and Elements
Minerals: solid chemical substances with uniform structures that form under certain temperatures and pressures.

37. 3 Different Ways that Rocks Can Form Leading to 3 Different Types of Rock
Igneous Rocks
Formed directly from magma.
Basalt: dark, high minerals, usually on ocean floor.
Granite: dominate type found. Turns into sand. Includes feldspar, mica, and quartz.
Intrusive Igneous: cools in place underground as it rises.
Extrusive: cools above the Earth’s surface.

38. Sedimentary Rocks
Form when sediments such as sand, muds, or gravels are compressed by overlying sediments.
Where fossils are found.

39. Metamorphic Rocks
When igneous, sedimentary or metamorphic rocks are subjected to high temperatures and pressures.
Slate, marble, and anthracite.

41. Weathering and Erosion
When rock is exposed to air, water, chemical compounds or biological agents (roots, lichens, burrowing animals).
Types:
Physical: mechanical breakdown.
Chemical: dissolving of chemical elements.

43. Acid Rain: sulfur is emitted into the atmosphere as a result of fossil fuel combustion, combines with oxygen and forms sulfur dioxide.
Sulfur dioxide combines with water vapor in the atmosphere to produce sulfuric acid.

45. Erosion: the physical removal of rock fragments from a landscape or ecosystem.
Result of:
Wind, water, and ice transport soil and other earth under the force of gravity.
Animals that burrow under the soil.
Deposition: the accumulation or depositing of eroded material.

46. Erosion is a natural process.
Human Impacts contribute to erosion:
Poor land use practices such as deforestation, overgrazing, unmanaged construction activity, and road building.
Eroded land can be deposited in other areas causing addition environmental problems.

48. Link Between Rock Cycle and Biosphere
Soil:
Link Between Rock Cycle and Biosphere
Soil formation takes place at the Earth’s surface.
Soil: mix of geologic and organic components.

49. Soil: Yeah : ))
Medium for plant growth.
Primary filter for water.
Habitat fro a wide variety of living organisms.
Filter chemical compounds deposited by air pollution and sewage.

51. Formation of Soil Takes 100s to 1000s of years!!
Combination of detritus and minerals.

52. 5 Things Determine Soil Properties
Parent Material: rock material underneath.
2. Climate: determines type of vegetation that develops(and breaks down).
3. Topography: surface slope and arrangement of a landscape.
4. Organisms: plants, animals and human activity.
5. Time: how long it has been around.

53. Soil Horizons and Properties
Soil Horizons: Layers in the soil.
O Horizon: at the surface, organic, layers of organic detritus.
A Horizon: Mixed, topsoil.
E Horizon: zone of leaching, eluviation zone. Not always present but when it is it is above the B.

54. B Horizon: subsoil, mineral material, little organic material.
C Horizon: Least weathered, similar to the parental material.

56. Physical Properties of Soil
Texture: determined by the percentages of sand, silt, and clay it has.

58. Porosity: how quickly soil drains.
Sand is the largest particle.
Clay is tightly packed together.
Silt is intermediate.
Clay is good for filtering contaminants whereas sand is not (water flows too quickly).

60. Chemical Properties of Soil
Cation Exchange Capacity (CEC); The ability of a particular soil to absorb and release cations.
Clay has a negative charge so can attract positive ions.
Too much clay can mean high water retention and waterlogging roots.

61. Base Saturation: measure of soil bases to soil acids.
Acids are detrimental to plant growth whereas bases promote growth.
A high CEC and a high base saturation are likely to support high productivity.

62. Biological Properties of Soil

63. Soil Degradation and Erosion
Degradation: the loss of some or all of the ability of soils to support plant growth.
Soil Erosion: topsoil is disturbed.
Plowing or removing vegetation can allow for soil to be removed by wind or water.
Compaction by machines and humans causes the soil to lose moisture then erode.

65. Distribution of Mineral Resources
Ores: concentrated accumulations of minerals from which economically valuable materials can be extracted.
Metals: conduct electricity or heat energy.
Reserves: The known quantity of the resource that can be economically recovered.

67. Types of Mining 1. Surface Mining Close to the Earth’s surface.
Strip Mining: removal of strips of soil and rock to expose ore.
Resource is extracted and the “mining spoils” or “tailings” are returned.

68. Open Pit Mining: large hole in the ground. Copper mines are common.
Mountaintop Removal: remove an entire top of a mountain with explosives. Tailings dropped in local rivers and streams.
Placer Mining: looking for metals and precious stones in river sediments.

69. 2. Subsurface Mining
Digging deep down and extracting resources.
Coal and diamond are common (some 2.2 miles deep)!

71. Mining Safety and the Environment
Roads
Erosion
Habitat Fragmentation
Habitat Destruction
Tailings deposited
Acids and metal contamination
Mercury deposition during Placer Mining
Acid mine drainage.

72. Mining Legislation
Mining Law of 1872 (General Mining Act): individuals and companies can recover ores or fuels from federal land.
Surface Mining Control and Reclamation Act of 1977: regulates surface mining of coal and the surface effects of subsurface coal mining. Mandates that land be minimally disturbed during the mining process and reclaimed after mining is completed.