Bellwork

•Using a circle map, brainstorm all the things you know about erosion, deposition, and landforms.

•You may include questions you would like to have answered about the above.

•Keep your circle map, you will add to it and turn it in at the end of class.

Landforms, Erosion and Deposition

•Prentice Hall Science Explorer

•Earth’s Changing Surface

•Chapter 3 (and other resources)

What is meant by landforms?

•a natural physical feature of the earth’s surface

•Examples: bay, butte, canyon, cliff, delta, hills, geyser, glacier, gulf, island, mountain, plain, peninsula, prairie, terrace, woods, valley, volcano

 

What is erosion?

•The process by which water, ice, wind or gravity moves weathered rock and soil.

•Different rocks and soil erode at different speeds based on their composition.

•The material moved by erosion is called sediment.

What is deposition?

•Process by which sediment is laid down in new locations.

Water Erosion & Deposition

•V-shaped valleys and canyons are caused by river erosion.

•Sediment deposited when a river flows into an ocean or lake is called a delta. The Mississippi Delta was formed by the Mississippi River.

Water Erosion continued

•Courses of rivers change over time forming floodplains, meanders and oxbow lakes, as erosion and deposition act on soils of different types (some eroding more quickly than others)

Water Erosion continued

•As groundwater (water found underground) erodes underground deposits of limestone, sinkholes can form.

 

Special cases of Erosion

•Mississippi was once covered by a warm tropical sea

–Which is why there are fossils of sharks, and whales, but not dinosaurs in Mississippi

–Some of these fossils have been uncovered by erosion

Special Case of Erosion

•Rock formations, like the one at the right, can be larger at the top because the top layer of rock is harder than the lower rock.

 

Special cases of Deposition.

•The petrified forest in Flora was created as deposited minerals fossilized the wood.

•When lava from an underwater volcano piles up to form an island, scientist can measure the island growth by measuring the soil depth and seeing how much is deposited over time.

Wrap up

•Without looking at your notes, add things you learned today to your circle map using the crayons that are being passed out.

•You will turn this circle map in when you are done, so be sure to put your name on it.