Introduction to Weathering and Erosion

Weathering and Erosion Weathering = change the appearance of something through long exposure of air/water/nature Erosion = removing pieces of rocks and transporting them to another by wind and water. Teacher Notes: Talk about their difference. Weathering is a process that breaks down the rock while erosion takes away parts of the rock. Such examples of weathering would be when water seeps into cracks of rocks and it turns into ice causing the rock to crack open. An example for erosion would be wind blowing on a piece of rock and little bits of the particles come off the rock.

Types of Weathering Physical Biological Chemical Ask kids to define physical, mechanical, and chemical ( there is no right or wrong answer). This is a way for the kids to brainstorm and gather ideas about what they are about to learn.

Physical Weathering The breaking of rocks by: wind or rain contraction water freezing thermal expansion This occurs in regions with extreme temperatures Physical weathering is when wind, rain, contraction, water freezing, and thermal expansion break the rock into pieces. this is physical weathering because it touches the rock to cause weathering of the rock. Most of the physical weathering happens in areas that have either REALLY hot or REALLY cold temperatures because it affects the rocks a lot. In the pictures here, the rocks are broken because ice inside and outside the rock cracks them.

Biological Weathering Rocks are broken down by living things or decomposed Broken by: Lichens Tree roots Ask the class what decompose means. Tree roots are a good example of biological weathering because often times, tree roots grow and rub against rocks: breaking the rocks. Does anyone know what decompose or decomposition means? Decompose means to have living things like leaves and dead animals be broken down and become part of the ground (the Earth) so when this happens the rocks are affected as well. Trees also grow in between large rocks, as seen in the picture, which breaks the rock.

Chemical Weathering The breaking of rocks when water and rocks interact with each other to create a chemical reaction. Rocks are broken by: water gases Ask the class: What are chemicals? And what is a chemical reaction? Explain to them that chemical weathering is when water and rock substances react with each other to change the form of rocks. Chemical weathering is caused by waters and gases.

What kind of rock weathering is this What kind of rock weathering is this? Biological because there are plants and trees growing in between the rock which breaks it apart.

What kind of rock weathering is this What kind of rock weathering is this? Physical/ mechanical because it involves water shaping/ breaking down the rocks

What type of weathering is this What type of weathering is this? Chemical because you can see the different colors of the rocks which means there has been a chemical reaction

Erosion is the process by which the surface of the Earth gets worn down caused by natural elements such as wind and glacial ice. The key to erosion is something called "fluid flow." Water, air, and even ice are fluids because they to flow from one place to another. Erosion What was the definition given in the beginning of the lesson about erosion? Tell the kids that erosion is a process by which the Earth gets its shape when sediments are broken down and carried away from water and wind (natural forces)

Compare Weathering and Erosion Similarities Weathering and erosion are both natural forces that break down rocks and shape Earth’s surface Both are continuous natural processes that happen over time Review what is weathering and what is erosion. Ask them find the similarities between weathering and erosion.

Contrast Weathering and Erosion Differences: Erosion breaks down rocks but it involves water and wind to move the broken particles to a new location Weathering breaks the rocks apart with natural forces but the particles stay next to each other What is contrast mean? It means differences. Tell the kids what makes erosion different from weathering. It is because Erosion carries the broken particles away to another location

Erosion Tell the class they will be watching a short video about erosion. Pass out a worksheet with questions that the kids must answer. After the video is over, correct the questions together as a class. End of lesson 1

Erosion Lab Objective: Demonstrate how water causes erosion. What to notice: the color changes Lesson 2: Began the skittles erosion lab. Before having the students go off doing their lab, first do a quick demo so that the students will not be confused on what they should do. Make sure to let them know what this lab is related and have the student understand what to do before setting them off to the lab themselve. They will do the lab for the whole lesson today.