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Science Ch. 8 Notes Lesson 1 Earth’s Layers: 1. Crust – outer layer, made of different kinds of rocks 2. Mantle – made of hot igneous and metamorphic rock 3. core – inner most layer, made of metal hot enough to melt 4. inner core – (center of core) packed so tightly, it remains mostly solid Landforms and Bodies of Water: p. 224-225 Landform = solid features found on Earth’s Crust - Glacier – large body of moving ice - Valley – low narrow area, sometimes forms when a river slowly cuts through rock - Plateau – a plain that is higher than the area around it - Mountain – formed when blocks of rock are pushed up or dropped down along the cracks in the Earth’s Crust - River – a natural stream of water that helps to shape the valley or plain it passes through - Hill – high rounded place - Plain – large, mostly flat area - Lake – forms when water slows enough to fill an area - Coast – land next to the ocean - Ocean – the salt water that covers the Earth’s surface

Lesson 2 Volcanoes

- volcanic eruptions can rapidly change the surface of the Earth. - When lava cools it becomes igneous rock, which becomes new crust for the Earth Earthquakes - sudden shifts between parts of Earth’s crust causes the ground to vibrate in all directions. Most earthquakes happen along fault lines (cracks in the Earth’s crust) - the vibrations of an earthquake move as waves up, down, back, and forth along the Earth’s surface. These waves can cause cracks in the Earth’s surface. Rubble can pile up in areas where crust moved.

Lesson 3 - Weathering = any action that breaks rocks into smaller pieces o Plant Roots – can grow into cracks in rocks. As the roots grow, they can split and break up the rocks. o Water – water gets into cracks in rocks and freezes (expands). The ice pushes against the sides of the rock and breaks the rock apart. - Erosion = The movement of weathered material o Water – rainwater can carry away soil from hill farm fields o Wind – wind carries sand particles through the air that rub on bigger rocks and break of tiny pieces of the rocks o Gravity – pulls rocks and soil downhill  mudflow – quick movement of very wet soil  rockslide – quick movement of rocks down a slope - Both weathering and erosion change landforms over a long period of time. Weathering breaks down rocks into smaller pieces. Erosion carries these pieces to a new place.