Earth’s Moving Plates Mr. Perez

Important Vocabulary Density Mesosphere Earthquake Plate Inner core Outer core Mantle Crust Lithosphere Asthenosphere

Clues to Earth’s Interior Geologists learn about the interior of our Earth by gathering… Indirect evidence from SEISMIC WAVES Waves travel faster through solid rock than liquid rock By sending seismic waves through Earth, scientists measure their speed and note differences in their path Earthquake: sudden release in Earth’s crust, causing Earth to shake Direct evidence from ROCKS Found in different places on Earth’s surface and made of different materials Rocks formed deep in the Earth are pushed up to the surface

Clues to Earth’s Interior The seismic clues and rock clues suggest that Earth is made up of layers of different kinds of materials.

Earth’s Layers The Earth consists of 4 main layers: Inner core Outer core Mantle Crust

Set up your notes like this: NAME OF LAYER: Definition Temperature Composition Thickness Fact(s)

Inner core Inner core: innermost layer of Earth (SOLID) Temperature: up to 9,000°F (hottest layer of Earth) Composition: Dense layer composed of mostly solid iron Thickness: about 1,250 km Fact: Under the greatest amount of pressure (force pushing on an area)

Outer core Outer core: layer of Earth that lies above the inner core Temperature: 4,000 - 9,000°F Composition: Composed of molten (liquid) metal Stops one type of seismic wave and speeds up the other Thickness: about 2,220 km Fact: This layer is responsible for creating Earth’s magnetic field

Earth’s Magnetic Field http://www.youtube.com/watch?v=yEYy_nVC4L0

Mantle Mantle: largest layer of the Earth Temperature: 1,600 - 4,000°F Composition: Composed of solid rock that flows like putty; iron, magnesium, aluminum, silicon and oxygen Thickness: about 2,900 km Fact: Contains convection currents that move magma below the Earth

Crust Crust: Earth’s outermost layer Temperature: up to 1,600°F Composition: Composed of solid rock; calcium, sodium and aluminum Thickness: about 0 – 100 km Thinnest under the ocean (oceanic crust): 0-5 km Thickest under the continents (continental crust) 0-30 km Fact: All of Earth’s surface features are part of the crust

Crust Oceanic crust is made of basalt, a dark colored rock with fine grains Continental crust is made of granite, a light colored rock with coarse grains

Earth’s Structures Although the Earth’s structure can be divided into 4 basic layers, they can be also divided by physical properties that change with depth below the Earth’s surface The deeper you go into the Earth, the following increase: Density Temperature Pressure

Earth’s Plates Even though the crust is different from the mantle, the uppermost part of the mantle moves like the crust. Lithosphere: rigid, upper part of the mantle and crust Asthenosphere: plastic-like layer below the lithosphere in the mantle Mesosphere: lower layer of the mantle that borders the liquid outer core

Mantle Divisions

Earth’s Plates Plates: sections of the Earth’s lithosphere and crust Move very slowly on the asthenosphere. Lasers and satellites can measure how far the plates move The earth is broken up into about 30 different plates.

Links http://www.education.com/study-help/article/earthscience-help-earth-mantle/ http://ed101.bu.edu/StudentDoc/Archives/fall05/malily/LayersofEarth.html http://pubs.usgs.gov/gip/dynamic/inside.html

Sources Florida Science Grade 6, Glencoe Science & McGraw Hill Publishing Google image search