Structure of the Earth Flashcard

What is the diameter of Earth?

Approx 12,800 Km

What is the outer layer of the Earth called?

The Crust

What is the next layer of the earth called?

Mantle

 

mantle or asthenosphere-the thickest layer of the earth, about 3000km thick, made up of rock melted to a thick,pastry texture, like peanut butter or toothpaste.

Remember that rock begins to change from a solid to a liquid at about 2000 degrees.

What is Lithosphere made up of?

The uppermost part of the mantle & the crust make up the Lithosphere

 

Lithosphere- the solid ,rocky outer crust of the earth, about 1-20km thick.

How do we know the structure inside the earth if no one has seen it?

Scientists have observed how , siesmic waves travel through the earth after an earthquake and have been able to build a detailed picture of the inside of the earth.

 

The way in which seismic waves travel through the earth is affected by the stucture of the earth.

Ho do we know the centre of the earth must be made of different materials to the crust?

By making  careful measurements, physicists have been able to measure the mass of the Earth and calculate it’s Density.

;

The Density of the Earth as a whole is much greater than the density of the rocks found in the crust.

Crust

;

;

Mantle

;

;

;

Core

Averages: about 6 km under the oceans; ; 35 km;under continental areas.

;

Starts underneath crust and continuesto about 3000 km below Earth’s surface. Behaves like solid, but is able to flow very slowly.

 

Radius about 3500 km.

Made of Nickle & Iron.

Outer core is liquid, inner core solid

 

How many parts make up the Earth’s Core?

Inner Core;-made up of earths heaviest materials, the inner core is solid. At about 5000 degrees it is;hot enough;to melt ;;run like water. But;the reason it is solid is that melts have to be able to expand, and the pressure of the weight of the outer core, mantle and lithosphere keeps the inner core frombeing able to expand, so threrefore it cannot become a liquid, even tho it is hot enough to melt. The inner core is about 1200 km across

;

Outer Core

What is the temperature at the centre of the Earth?

Between 5000 oC and 7000 oC

Get instant access to
all materials

Become a Member