Agenda Aug 2 What am I learning today? How do physical forces shape the Earth’s landscape? What am I doing today? Power point with notes; landforms DBQ How will I show that I learned it? 4 box synetics summary

Write Examine the image below. Warm up Aug 2 Write Write 3 observations and 3 related inferences about the image.

Forces That Shape the Earth

Where do forces that shape the earth begin? Core Mantle Crust

Why should we care about earth’s structure Tectonic plate movements The two physical processes that build and shape landforms Volcanic activity

Tectonic Plates Large pieces of earth’s crust found beneath continents and oceans Pieces float and move on the liquid mantle

Tectonic plates MOVE! Gave rise to idea of a supercontinent called Pangaea Continental drift theory: Pangaea broke apart and continents drifted to their current position

What are the consequences of plate movements? Build mountains Cause earthquakes

How are mountains built? Tectonic plates collide “head-on” If plate does NOT break, creates fold mountains like the Appalachian Mountains

What happens if the plates break in the mountain building process? Fault block mountains Pressure builds between the blocks of crust which tilt and tip up to form mountains like the Sierra Nevada in California

How do plate movements create earthquakes? Friction locks plates into place for long periods Pressure builds beneath the plates When pressure is too great, plates unlock, move and release energy we feel as earthquakes

Volcanic Activity Found along edges of tectonic plates Magma sometimes pushes to surface through cracks to create a volcano

Effects of Volcanic Activity Build mountains, islands “Blow off top” tearing down a mountain Ash can bury vegetation, towns, etc. Ash can block sun and cool global temperatures

The Pacific Ring of Fire

Forces on Earth’s Surface Forces inside the earth create. Forces on the surface of the earth reshape. 1) Weathering is a process that breaks rocks down into tiny pieces. 2) Erosion is the removal of small pieces of rock by water, ice and wind.

Weathering Chemical weathering Rock is changed into new substance More common in warm, moist climates

Weathering Mechanical weathering Does NOT change rock composition, only size of rock Common in dry areas with both hot and cold temperatures

Erosion Weathered material is moved 4 agents of erosion: wind, water, ice, and gravity

Wind Erosion Strips a fine layer of soil Grinds away at rocks

Water Erosion Erodes vertically and horizontally to create V-shaped valleys Faster flow creates greater erosion

Ice/Glaciers Moving mass of ice that carves out U-shaped valleys Transports large quantities of rock and soil which it deposits to create new landforms such as moraines

Gravity Movement of material (soil, rocks) from higher to lower ground Examples: landslides, rock slides, mudslides

Close – 4 box synectics summarizer Complete the handout using each of the 4 words below: Erosion Weathering Volcanoes earthquakes