Lesson 2Wearing Down Earth’s Surface

Pages C14-C18

Weathering

• Mechanical • Chemical

Mechanical

• Breaking larger rocks into smaller pieces called “sediment”

• Mechanical Weathering - Geology For Kids - By KidsGeo.com

• Causes: wind, water, living things

• DOES NOT CHANGE MATTER!

Chemical

• Rocks change into new matter

• Water is the main factor

• Water dissolves some chemicals from the air and soil to form a weak acid.

• Limestone and Marble- easily dissolve

• • Prince Edward Island Red Sands

Caves

• Weak acids formed in rainwater seep into the ground

• Acids dissolve rock.• Holes are formed• Over time holes get bigger= CAVE

• CAVE ANIMATION• CAVE DIAGRAM

Erosion

• CAUSE/weathering

• EFFECT/erosion

• Carrying away of sediments by moving water, wind, or moving ice

• EROSION SONG

Erosion

• Main cause- moving water

• Can increase the size of a river channel

Glacial Deposits

Sinkholes

• Sinkhole Animation

Landslides

• Picture of Landslide

• Causes: strong rain, gravity, earthquakes, volcanoes