The document summarizes the key layers that make up Earth's structure, from crust to inner core. It then discusses plate tectonics and how the movement and convergence of tectonic plates results in one plate being pushed under another. Evidence of past tectonic motion comes from matching rock types and fossils on opposite sides of oceans.

1. crust The crust is the thinnest layer of the Earth's structure. It is composed mainly of basalt and granite , which are igneous rocks. The crust is made of vast slabs of rock known as " plates ."

2. mantel The mantle is the thickest layer of the Earth's structure at around 1,450 miles. Most of it is molten rock, but nearer the surface of the Earth it solidifies.

3. outer core The outer core is liquid and is thought to be made mainly of iron and nickel. The Earth's magnetism is caused by the inner and outer cores.

4. inner core The inner core can be described as a solid ball. It is thought to be made mainly of iron and nickel. Even though temps can exceed 5,000 degrees, the inner core remains solid because of the extremely high pressure.

6. Converge is a large word that scientists use to describe two objects that come together. In the case of plate tectonics, the two objects coming together are large plate-like pieces of the Earth’s crust. As these two plates push against each other, one is ultimately forced down beneath the other.

8. Our first evidence of tectonic motion is based on similar fossils and rock types on opposing sides of the ocean

15. Introduction to Erosions The earth's surface is constantly being worn away by a process called weathering . http://www.cosmicpair.com/Rock_Matrix/Erosion_files/shapeimage_1.jpg

16. Physical Weathering is the mechanical breaking down of rocks. What are some examples of how this happens?

17. WIND http://www.nycaudubon.org/takeaction/local/photos/Plumb_Beach_Wind_Erosion.jpg

18. WIND EROSION & DEPOSITION Sand is formed by the breaking down of rocks over long periods of time. Abrasion is the grinding away of a surface by wind-blown sediments. Very fine-grained sediment deposited by wind is called loess.

19. DUNES Dunes are mounds of wind-deposited sand. Dunes begin to form where obstacles slow wind energy.

20. PRECIPITATION RAIN http://www.ngsprints.co.uk/images/M/696695.jpg

21. SHORELINES A shoreline is where land meets a body of water. Wave-cut terraces form when waves erode a sea cliff, forming a nearly level platform at water level. SHORELINE FEATURES Sea cliffs have very steep slopes and form when waves erode and undercut rock. He adlands are areas of resistant rock that extend into the water.

22. Sea arches form when waves erode through a sea cave. Sea stacks form when waves erode away the top of a sea arch. Sea caves form when waves erode deep holes into the weaker rock of a cliff.

23. C:ocuments and Settingsormartrocal Settingsemporary Internet Filesontent.IE515HMWAI6_plant_on_rock[1].jpg PLANTS

24. Alpine glaciers carve out rugged landscapes. Glaciers flow on a layer of water, ice melted by the pressure of the glacier’s weight. The top flows faster than the bottom, creating crevasses. A glacier is a huge mass of accumulated ice and snow that moves due to gravity.

27. ARETES MORAINES HORN CIRQUE GLACIAL LANDFORMS

28. Terminal moraine Terminal moraine The front of a glacier which contain massive amounts of sediment.

29. MASS MOVEMENT The movement of rock, soil or snow downslope due to gravity. Angle of repose is the steepest slope that material remains stable. This angle depends on the type of material, characteristics of the underlying surface, and the level of moisture. Adding water to a stable slope can make it unstable.

30. RAPID MASS MOVEMENT Rock fall Mudflow Avalanche Lahar

31. SLOW MASS MOVEMENT Slow mass movement can occur over days, weeks or years and can be identified by bending trees, fences and roads. Creep

32. erosion - gradual change in landforms through wearing away of soil and rock caused by wind , water , or some other natural force . glacial erosion Erosion caused by water; millions of years ago before the Grand Canyon was formed, the Colorado River was a quiet river streaming through the land. Imagine that the river started up here! Believe it or not, this rock formation resulted from wind erosion. Smaller, lighter chunks of rock broke off and blew away until this formation was all that remained. glacier

33. Chemical Weathering is the process that breaks down rocks by changing their chemical composition. What are some examples of how this happens?

34. http://www.supergreenme.com/data/images/11/acid_rain.jpg ACID RAIN

35. http://image24.webshots.com/24/2/88/78/37628878kbQOJQ_fs.jpg LICHENS

36. http://www.dorlingkindersley-uk.co.uk/static/clipart/uk/dk/sci_earth/image_sci_earth051.jpg ACIDIC WATER

37. Evidence of Erosion What are some clues that erosion has occurred in this picture? Move rectangles to reveal the answers. http://www.kented.org.uk/ngfl/subjects/geography/rivers/images/erosion%20picture%201a.jpg