True or False: The Earth’s surface has stayed the same for thousands of years

The Earth’s surface is always changing! True or False: The Earth’s surface has stayed the same for thousands of years False The Earth’s surface is always changing!

Weathering and Erosion Wind Water

The breaking down of Earth’s crust into smaller pieces. Weathering The breaking down of Earth’s crust into smaller pieces. Weathering causes soil formation

Water causes weathering What evidence of weathering do you see in this picture?

Wind causes weathering Why wasn’t this mass of land weathered away? What evidence of weathering do you see in this picture?

Describe how ice causes weathering?

How do we prove weathering takes place How do we prove weathering takes place? What are the 2 W’s that cause weathering? Each group will need a sugar cube (representing a big rock), a pan, and a spray bottle. The whole class will use the two fans in the classroom to represent wind. Each student will represent a “hurricane” (Don’t be mistaken—light rain can also cause weathering). Take turns to “rain” on the sugar cube (the big rock). Each student (hurricane) sprays on the sugar cube (big rock) for 30 seconds. What happened to the rock?

How do we prove moving water causes weathering? What are examples of moving/running water? Put a rock in a water bottle or jar. Shake the bottle for 2 minutes. What do you observe?

Let’s see more evidence of weathering! Watch a brainpop.com video about it. Read pages 136, 137 of your book. We will go outside to look for these proofs of weathering.

What is erosion? You will need a “rock”, “rain” (spray bottle), Jenga blocks, and a tray. Groups 1, 2, 3,4, and 5 will tilt their tray by using 0, 3, 6, 9, 12 blocks respectively. Spray or “rain” on the “rock”. Observe what happens to the loose sediment.

What evidence of erosion do you see in this picture? The process by which water, ice, or wind moves fragments of rock and soil. What evidence of erosion do you see in this picture?

Let’s show erosion caused by ice. Let’s make a mixture of water and dirt. Freeze the mixture. What do you think will happen when we take the frozen mixture of dirt and water out of the freezer and put it outside at normal room temperature?

Erosion is Movement of Sediment! This process, known as Erosion, is gradually wearing down the surface of the earth. Erosion is the process by which weathered rock and soil (sediment) are moved  from one place to another. Erosion carves the Earth's surface creating canyons, gorges, and even beaches. What do you think has caused this rock to look this way?

Wind Erosion As the wind blows it picks up small particles of sand/sediment and blasts large rocks with the abrasive particles, cutting and shaping the rock.

Water Causes Erosion runoff, rivers and, streams Creates MOST of the changes in the Earth's landscape!

Water causes Erosion When rain falls to the Earth it can evaporate, sink into the ground, or flow over the land as Runoff. When it flows over land, erosion occurs. Runoff picks up pieces of rock and "runs" downhill cutting tiny grooves (called rills) into the land. Rivers and streams are a constant flow of runoff- they constantly weather and erode!

Ice Causes Erosion Glaciers wear down the landscape; by picking up and carrying debris that moves across the land along with the ice.

Ice Causes Erosion Glaciers can pick up and carry sediment that ranges in size from sand grains to boulders bigger than houses. Moving like a conveyor belt and a bulldozer, a single glacier can move millions of tons of material!

How do we prevent erosion?

Plants CAN PREVENT erosion

Your turn! We will discuss the questions from your Study Guide. Read pp. 138 and 139 Watch a video on weathering and erosion