Science 9 weeks Test Review

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Earth's Structure-

pg 1 layers of the earth

Crust

There are two different types of crusts; the continental crust and the oceanic crust.

we live in the crust

the crust has Tectonic plates which shift and collide to form volcanoes, mountain ranges, valley, etc.

we live in the continental crust which is the continents.

the oceanic crust is the ocean and is denser than the continental crust.

It is hard and rigid

It is the outermost and the thinnest layer, only a few miles thick

Mantle

it is subdivided into two regions, upper and lower

the dense layer is made of hot semisolid rock

it is right under the crust'

the top part of the mantle is called the lithosphere

under the lithosphere is the asthenosphere

it is the thinkest layer of the earth

not fully liquid but semisolid

Inner core

the inner core is extremely hot and made out of mostly iron and nickel

it is right smack in the middle

the outer core covers the inner core

it is a pure hot stone which is made out of really all heavy things and magma

it is about 750 miles in diameter

Outer core

the outer core is the only liquid one out of all the layers of the earth

it is a sea of mostly iron and nickel

it is 1400 miles think

it wraps around the inner core like a blanket

it is almost right smack in the middle but the inner core is in the middle

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