Inside the Earth

Why is geology important?

Layers of the Earth If we could take a chunk out of the Earth, we would see that it is made up of different layers.

Layers of the Earth Earth is made up of 3 main layers Crust Mantle Core Each layer has it’s own individual composition and physical properties.

Physical Properties and Composition Composition= what it’s made of Physical properties= characteristic that is unique and helps to identify the substance (temp, size, shape, color) Example: Chocolate Chip Cookies Composition- flour, eggs, sugar, chocolate chips, baking powder, butter Properties- round, rough, sweet, tan and black, hot, lumpy,

Layers of the Earth(p90) CRUST Physical Properties: outermost layer thinnest layer (5-70km thick) Surface temperature 1% of Earth’s mass where we live touches the atmosphere Composition: consists of loose rocks & soil

Crust Very thin

2 Types of Crust Continental Crust: dry land, granite less dense Oceanic Crust: ocean floor, Basalt, thinner than cont. crust but more dense

Layers of the Earth MANTLE Physical Properties: thickest layer (2900km thick) 1600-4000 F 66% of earth’s mass flowing Composition: Molten rock Magma

Layers of the Earth CORE Physical properties: HOT! 4000-8000 F Very dense High pressure 4000 miles from surface 33% of Earth’s mass About the same size as Mars Composition: Iron and Nickel (metals)

What have you noticed about temperature and pressure? As you get deeper inside the Earth, temperature Increases As you get deeper inside the Earth, pressure Increases

Layers of the Earth The 3 main layers of the Earth can be divided further by the way they “act” within the Earth and by their different physical properties.

Lithosphere Crust and upper Mantle outermost layer – includes crust and upper mantle rigid divided into pieces or tectonic plates Rocks and soil

Asthenosphere Middle Mantle composed of solid flowing rock layer on which pieces of lithosphere move on top (solid rock that flows) Think of it like caramel

Mesosphere Bottom Mantle strong, lower part of the mantle layer between asthenosphere and core

The Core Outer and Inner The core is divided into two parts Outer Core: Liquid iron and nickel that’s spinning Inner Core: Solid iron and nickel Solid because of all the pressure of the rest of the Earth surrounding it.

How do we know? Seismic waves produced by earthquakes travel at different speeds through solid rock and liquids

Layers of the Earth