1. Chapter 2 Physical Geography: A Living Planet

2. CONTINENTAL DRIFT THEORY
Originally suggested by Francis Bacon in 1620
Presented theory in 1912 by Alfred Wegner of Germany
Theory states that all continents were once a super continent that divided and slowly drifted apart

3. Where are we? 93,000,000 miles from the Sun 3rd Planet in from the Sun
24,900 miles in circumference and 7900 miles in diameter
Only planet in Milky Way solar system that can sustain human life

4. THE MILKY WAY Our Solar system consist of the sun 8 planets
1 dwarf planet (Pluto)
Other celestial bodies that orbit the sun
Comets > spheres covered with ice and dust that leave trails of vapor as they race through space
Asteroids > large chunks of rocky material found in space
By size: Pluto (dwarf), Mercury, Mars, Venus, Earth, Neptune, Uranus, Saturn, Jupiter

5. Section 1: The Earth Inside and Out
1. The earth is the only living planet…
Continents –
landmasses above water on earth

6. 2. The earth consists of
plates
that float…

7. 3. The theory of continental drift explains the formation of continents

8. Inside the Earth
Core
– center of the earth (inner core- liquid iron and nickel; outer core – solid iron and nickel)
Mantle
– several layers surrounding the core
Crust
– thin layer of rock at the earth’s surface

9. Biosphere
The part of the earth where plants and animals live (atmosphere, lithosphere and hydrosphere)

10. On and Above the Earth
Atmosphere –
layer of gases surrounding the earth (contains oxygen, protects the earth from radiation and space debris, and provides a medium for weather and climate

11. Lithosphere
Solid rock portion of the earth (includes crust and uppermost mantle, ocean floor, etc.)

12. Hydrosphere
Made up of water elements of the earth (oceans, seas, rivers, lakes and water in the atmosphere)

13. Section 2: Bodies of Water and Landforms
Human Perspective
The earth is unlike any other observable planet in our solar system. It is a living planet.
Where there is water there is LIFE.

14. Section 2: Bodies of Water and Landforms
The ocean is interconnected and covers over 70% of the earth.
Divided into 4 main parts. Pacific (largest), Atlantic, Arctic and Indian

15. Ocean Movements Currents- like rivers flowing through the ocean
Waves- swells produced by winds
Tides - regular rises and falls of the ocean created by the gravitational pull of the moon or the sun

16. MOTION OF THE OCEAN The ocean distributes heat.
Winds blow over the ocean and are either heated or cooled by the water, moderating the temperature of the air over the land.

17. Hydrologic (water) Cycle
The water on earth is continuously circulated between the atmosphere, the oceans, and the earth

18. LAKES, RIVERS, & STREAMS
Lakes hold more than 95% of all fresh water on earth.
Rivers and streams
move water to or from
larger bodies of water.

19. LAKES, RIVERS, & STREAMS
Saltwater lakes are created when creeks & rivers carry salts
into a lake, and there is no outlet to carry the salt away.
Largest: Caspian Sea (West Asia)

20. Drainage Basin -
Area drained by a major river and its tributaries

21. Ground Water–
water held in the pores of rocks
Water Table –
the rim level at which rocks are saturated

22. Oceanic Landforms (topography)
The ocean floor and the continents have a continental shelf and slope
The ocean floor is similar to the land above water.

23. continental shelf

24. Continental Shelf
Earth’s surface from the edge of a continent to the deep part of the ocean

25. Continental Landforms
Naturally formed features on the surface of the earth are landforms

26. Topography & Relief
Relief refers to the difference in elevation of a landform from lowest to highest point
Mountains, hills, plains, canyons
The combination of the surface shape and composition of the landforms and their distribution in a region > topography
Topographic Maps show the landforms with their vertical dimensions and their relationship to other landforms.

27. Section 3: Internal Forces Shaping the Earth
The earth’s crust consists of number of tectonic plates
tectonic plates - enormous moving pieces of the earth’s lithosphere
Spreading; subduction; collision; sliding past each other in a shearing motion

28. Movement
of the plates
produces
earthquakes
and volcanoes
Fault – fracture in the earth’s crust where plates move past each other

29. Types of boundary movements:
Divergent – plates move apart, spreading horizontally (i.e. Saudi Arabia & Egypt making Red sea wider)

30. Types of boundary movements:
Convergent – Plates collide, causing either one plate to dive under the other or the edges of both plates to crumple (i.e. South Asia forming the Himalayas)

31. Types of boundary movements:
Transform – plates slide past each other (i.e. San Andreas Fault in California)

32. Volcanoes – crack in the earth’s surface where magma and gases pour out Benefits > fertile soil & energy
Lava –
magma that has reached the earth’s surface

33. measures the size of the waves created by and earthquake
Earthquake – Violent movement of the earth as the plates grind or slip past each other at a fault
95% around Pacific Rim (Ring of Fire)
Along plate boundaries
Seismograph –
measures the size of the waves created by and earthquake
Largest Earthquake measured> Kermadec Island, 8.9

34. Epicenter
Point directly above the focus of an earthquake on the earth’s surface
Richter Scale –
uses information collected by seismographs to determine the strength of an earthquake

35. DAMAGE
Landslides
Fires
Collapsed Buildings
Tsunami (speeds up to 450 mph and waves 100 feet tall)

36. Tsunami
A giant wave in the ocean caused by an underground earthquake

37. The most active volcano and earthquake zone on earth
The Ring of Fire
The most active volcano and earthquake zone on earth

39. “Hot Spots”
Volcanoes that are far from the margins of the tectonic plates are located on “Hot Spots”.
Hot springs & geysers are other features that indicate areas where the crust is thin.

40. External Forces Shaping the Earth
Human Perspective:
In Egypt, a seasonal dry wind is called Khamsin (50) for the number of days the season occurs. These wind-driven sandstorms cause serious problem for the people of the region.

41. External Forces Shaping the Earth
Weathering and erosion alter the surface of the earth
Weathering – physical and chemical processes that change the characteristics of rock on or near the earth’s surface

42. Example: road construction
Sediment – Small pieces of rock created by weathering (mud, sand or silt)
Mechanical Weathering –
processes that break rock into smaller pieces (doesn’t change the composition of rock, but the size)
Example: road construction
4 causes > human activity,
plants, frost, ice crystal in
cracks of rocks

43. Chemical Weathering –
occurs when rock is changed into a new substance as a result of interaction between elements in the air or water and minerals
(example – iron rusting)

44. Erosion
Occurs when weathered material is moved by the action of wind, water, ice and gravity

45. Water Erosion
The motion picks up loose material and moves it downstream
Delta –
sediment is deposited in a fan-like landform when a river enters an ocean

46. Wind erosion
Wind speeds have to reach 11 mph before fine sediments can be moved.
Depending on the types of wind, different types of landforms can be formed:
Loess, sand dunes, rock structures.

47. wind erosion
Loess – windblown silt and clay sediment that produces very fertile soil

48. Glacial Erosion
Glacier - a large, long-lasting mass of ice that moves because of gravity
(Form in mountainous regions)
Glaciation –
changing of landforms by slowly moving glaciers
Moraine –
rocks left behind from a glacier that form a ridge or hill

49. BUILDING SOIL HUMUS - Organic material in the soil.
Esker > snakelike ridge
Created by melted ice

50. Kettle > depression in the ground created by blocks of trapped ice in the sediment that melts. They can fill with water to form lakes.

51. Factors that determine soil fertility:
Weathering and erosion help form soil. Soil consist of a loose mixture of weathered rock, organic matter, air, and water that supports plant growth
Factors that determine
soil fertility:
Parent Material
Relief
Organisms
Climate
Time

52. The variety – and the climates in which they are found – determine the types of vegetation that can grow in a location. Agricultural activities, such as farming, ranching, and herding, depend on this complex relationship.