There are 2 ways to divide the layers of the earth..... Physical layers Compositional layers

Earth’s interior is divided into layers: the crust, mantle, & core, based on composition. Although the Earth’s crust seem stable, the extreme heat of the Earth’s interior causes changes that slowly reshape the surface.

CrustMantleCore

Outermost layer of earth made of rock that forms earth’s outer skin

5 to 100 km thick, average thickness is 35 km

thinnest layer less than 1% of Earth’s massMost of composition of crust:

oxygen, silicon, and aluminum

Oceanic Crust crust beneath the oceans consist mainly of dense rock (basalt -

dark in color) 5-8 km thick

Continental Crust crust that forms the continents consist mainly of less dense rock

(granite - lighter in color) 30 km average thickness

layer of rock between crust and core

2900km thick, 67% of Earth’s mass Magma from volcanoes comes

from mantle Composition - silicon, oxygen, iron

and magnesium physical conditions in mantle

change because pressure and temperature increase with depth temp ranges from 870 ºC to 2,200ºC

Convections Currents!

Hot columns of mantle material rise slowly through the asthenosphere

Innermost layer of the Earth 6800 km in diameter (3,400 km from

outside edge of core to center of core) 1/3 of Earth’s mass, 15% of its volume Temperature ranges from 2,000 ºC to

5,000ºC Consist of 2 parts; Inner Core and Outer

Core

The upper part of the mantle (upper part does not flow like the lower part) and the crust together form a rigid layer called the lithosphere.

Lithos is greek for stone, 100 km thick

Made of tectonic plates

The asthenosphere is a soft layer of the mantle on which pieces of the lithosphere move. 250 km thick asthenes is Greek for soft or weak

Rock that is semi solid, plasticky, kind of the consistency of peanut butter.

Heat travels by convection currents

The mesosphere is located in the lower mantle.

It is completely solid2,550 km thick

Outer Core layer of molten metal (iron and nickel)

beneath the mantle surrounds the inner core 2,200 km thick

Inner Core dense ball of solid metal (iron and nickel) extreme pressure from layers above 1200 km, from outside edge of inner core to

center

The tectonic plates are pieces of the lithosphere that fit like pieces of a jigsaw puzzle and move on top of the asthenosphere

May Consist of both Continental and Oceanic Crust

Atmosphere: .001g/cm^3

Water: 1.0g/cm^3

Crust: 2.7-3.0 g/cm^3

Mantle: 3-9 g/cm^3

Core: 9-13 g/cm^3

Seismic waves