Layers of the Earth

• continental crust - portion of the earth's crust that is not covered by the ocean
• crust - thinnest and outermost layer of the Earth
• crust - up to 100km below sea level
• continental crust is made up of granite
• oceanic crust is made up of basalt
• oceanic crust - portion of the crust under the ocean
• continental crust is less dense and thicker than oceanic crust
• asthenosphere - region made of semi-solid rocks
• lithosphere - region made of solid rocks
• lithosphere - includes crust and the upper solid part of the mantle
• mantle - thickest layer
• asthenosphere - divided into a soft upper layer and a hard lower layer
• mantle - made mostly of molten rocks (magma)
• outer core - made up of liquid iron and nickel
• inner core - made up of solid iron and nickel
• mantle - extends about 2,900km from the Earth's surface
• outer core - this layer of the Earth is 2250km thick and can be found 2,900km BELOW; it also has a temperature of approximately 2000 degree celsius
• inner core - has a radius of 1,300km; 5000 degree celsius
• pressure freezing - because of this process, the inner core is believed to be solidified due to tremendous pressure that it has been experiencing from the extreme temperature
• asthenosphere - where rocks begin to melt
• oceanic crust - 7-10km thick; sima
• continental crust - 40-60 km thick; sial
• convection currents - movement of magma within the mantle