Earth's internal heat and Structures

Question 1

• The thin outermost layer that wraps around the Earth
• Thickness ranges from 5 to 70 km
• Temperature ranges from 200 to 1,000 °C

Continental crust makes up the land on Earth, it is thicker (32-70 km), less dense and mostly made up of granite.

The oceanic crust makes up most of the ocean, it is thinner (5-8 km), denser and mostly made up of basalt.

Answer 1

CRUST

Question 2

• Found below the crust with a semi-liquid form and makes up 84% of the Earth’s volume.
• Thickness is about 2,900 km.

Lithosphere makes the lower crust and upper mantle, it is 100 km thick and composed of 15 major tectonic plates.

Asthenosphere is where the fluid form of the mantle is more evident.

The mesosphere is the deepest part and temperature is so high.

Answer 2

MANTLE

Question 3

Lies at the center of the Earth Thickness is about 3,430-3,730 km

Outer core lies beneath the mantle and is made up of liquid iron and nickel.

It is 2,200 km thick and has a temperature of up to 6,100°C
Inner core is the deepest layer and is made up on and nickel.

It is 1,230-1,530 km thick and has a temperature of up to 5,505°C

Answer 3

CORE

Question 4

• internal heat energy that gradually gathered through dispersion during the early Earth’s formation
• major contributor of this heat is the accretional energy- the energy deposited from the early Earth

➤ constantly lost to the outer silicate layers due to convection and conduction

Answer 4

PRIMORDIAL HEAT

Question 5

• thermal energy as a result of spontaneous nuclear disintegration
• involves the disintegration of radioactive elements like Uranium, Thorium, and Potassium

Answer 5

RADIOGENIC HEAT

Question 6

• happens when in the Earth’s surface and it directs the thermal settings in almost entire solid particles
• carries heat from Earth’s core and radiation from the sun through the movement of heat with colliding molecules

Answer 6

CONDUCTION

Question 7

• transfer of heat by the movement of mass and is more effective
• convection current in the mantle happens due to the movement of tectonic plates

Answer 7

CONVECTION

Question 8

• least important mode of heat transport on Earth
• process of heat exchange between the Earth and the Sun as well as the different layers of the Earth going to the surface

Answer 8

RADIATION