1. Unit 3 Lesson 1 How Do Weathering and Erosion Shape Earth’s Surface?
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2. Unit 3 Lesson 1 How Do Weathering and Erosion Shape Earth’s Surface?
Florida Benchmark
SC.4.E.6.4 Describe the basic differences between physical weathering (breaking down by wind, water, ice, temperature change, and plants) and erosion (movement of rock by gravity, wind, water, and ice).
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3. What Can Break a Boulder?
Unit 3 Lesson 1 How Do Weathering and Erosion Shape Earth’s Surface?
What Can Break a Boulder?
The process of rock breaking apart is called weathering.
Many things cause weathering.
Gravity, flowing water, blowing sand, living things, ice, and chemicals can cause weathering.
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4. Unit 3 Lesson 1 How Do Weathering and Erosion Shape Earth’s Surface?
Rocks on the Move
Weathering is the beginning of a series of changes that often happens to rocks on Earth’s surface.
The process of moving weathered rock from one place to another is called erosion.
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5. Unit 3 Lesson 1 How Do Weathering and Erosion Shape Earth’s Surface?
Rocks on the Move
Moving water is one of the most common causes of erosion.
Fast-moving water and gravity can cause rocks to move downhill.
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6. Unit 3 Lesson 1 How Do Weathering and Erosion Shape Earth’s Surface?
Rocks on the Move
As the water in a river slows down, bits of weathered rock are dropped. These bits of rock are called sediment.
The dropping of weathered rock by wind or moving water is known as deposition.
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7. Unit 3 Lesson 1 How Do Weathering and Erosion Shape Earth’s Surface?
Rocks on the Move
Rivers carry rocks and other sediment from upstream to the mouth of the river.
As rivers carrying sand and silt reach the ocean and slow down, sediment is dropped.
Over time, the sediment forms a delta.
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8. Unit 3 Lesson 1 How Do Weathering and Erosion Shape Earth’s Surface?
Rocks on the Move
What size of sediment drops out first? What size drops out last?
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9. Wind Wind can carry soil and other sediment near and very far away.
Unit 3 Lesson 1 How Do Weathering and Erosion Shape Earth’s Surface?
Wind
Wind can carry soil and other sediment near and very far away.
Winds may deposit a lot of sand in one area.
Over time, the sand builds up and forms dunes. Sand dunes often are found near sandy beaches.
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10. Unit 3 Lesson 1 How Do Weathering and Erosion Shape Earth’s Surface?
Ice
Huge sheets of ice are called glaciers. They are found in very cold places.
As glaciers flow, they move boulders, rocks, and sediment.
When the glacier melts, the sediment forms many landforms, including moraines.
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11. Unit 3 Lesson 1 How Do Weathering and Erosion Shape Earth’s Surface?
Gravity
Gravity can cause rocks and sediment to slide down mountains and cliffs. Sometimes it falls all at once in an event called a landslide.
Landslides often occur in mountain ranges.
The steeper the mountain slope, the more likely the rocks are to fall.
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12. Water Flowing water and ocean waves can break rocks apart.
Unit 3 Lesson 1 How Do Weathering and Erosion Shape Earth’s Surface?
Water
Flowing water and ocean waves can break rocks apart.
Ocean waves cut cliffs, form caves and sea arches, and carry away and redeposit sediment.
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