Earth’s Landforms Chapter 1 Lesson 1

Where do Landforms come from? Plate tectonics Large, slow moving plates that make up Earth’s surface. When moved, they carry continents and the ocean floors!

Where do Landforms come from? PANGAEA & Continental Drift SUPERCONTINENT! Continental drift theory is the belief about what broke Pangaea up into the seven continents.

Where do Landforms come from? Mountains: Formed when plates push together, crumble and fold. Also when plates push together and one moves over the other. Ex. Himalayas, Cascade Mts.

Where do Landforms come from? Earthquakes….. Caused by the movement of tectonic plates. Most common around fault (break in Earth’s surface where movement can occur). Ex. San Andreas Fault

THINK ABOUT THIS…… Two cars driving VEEERRRRYYYYY SLLLOOOWWW bump into one another. Do the passengers in the car feel the bump? DUHHHH. Now multiply the size of those cars by 100,000 (tectonic plates). Will the bump feel larger or smaller?????

Volcanoes FORM: KINDS OF VOLCANOES SHAPED EARTH When two plates push together and one goes up and the other goes down. Lower plate melts into magma. KINDS OF VOLCANOES Shield volcano, cinder-cone mountain SHAPED EARTH Add land when the lava cools and hardens

THINK ABOUT THIS…… Water on the stove… Water gets hotter and hotter (tectonic plate) until it……. BOILS!! (volcanic eruption)

EARTH’S SURFACE Weathering Wind and Water Process of breaking up rocks into smaller pieces called sediment. Wind and Water Two major forms of weathering

Erosion: Process of moving sediment from one place to another Deposition Process of dropping sediment into a new location Deposits add to the floodplain (the land next to a river)

People Shape the Land People use floodplains for farming Settle near water…..why? Reshape waterways Ex. Building dams, creating lakes Direct water into dry places Irrigation How else do people affect the shape of the land???

GROUP QUESTIONS HOW DO PLATE TECTONICS CHANGE THE SHAPE OF THE LAND? (3 WAYS) HOW DOES WEATHERING AFFECT THE LAND? WHATS THE DIFFERENCE BETWEEN EROSION AND DEPOSITION? HOW DO VOLCANOS CHANGE THE LAND AROUND THEM?