Interior of the Earth

Question 1

What does ‘Chemical Composition’ refer to?

Answer 1

The chemical composition of a layer refers to what it is made of (the arrangement of particles). It refers to the elements or compounds that make up each distinct layer of the Earth.

Question 2

Based on the chemical composition, how many layers does earth have?

Answer 2

1. Crust - oceanic and continental
2. Mantle - upper and lower
3. Core - inner and outer

Question 3

Based on the chemical composition, describe the properties of the crust.

Answer 3

1. Outermost layer of the Earth
2. Hard skin of a rock
3. Has two types - continental and oceanic
4. Around 0-45km thick
5. Brittle in nature
6. Mean density is 3g/cm3
7. Nearly 1% of Earth’s volume
8. Nearly 0.5% of Earth’s Mass

Question 4

Describe the properties of the continental crust.

Answer 4

1. 30kms think
2. SiAl
3. Lighter
4. Thicker
5. Granite Rocks

Question 5

Describe the properties of the oceanic crust.

Answer 5

1. 5kms think
2. SiMa
3. Heavier (denser)
4. Thinner
5. Basaltic Rocks

Question 6

Based on the chemical composition, describe the properties of the mantle.

Answer 6

1. Ranges from around 45-2900km thick
2. Contains approximately 84% of Earth’s volume and 67% of Earth’s mass
3. Density is around 3.3 - 5.4g/cm3
4. Has two parts - Upper Mantle (hard rocks) and Lower mantle (soft)
5. SiMa

Question 7

Based on the chemical composition, describe the properties of the core.

Answer 7

1. Ranges from 2,900km to 6,317km deep inside Earth
2. Contains nearly 15% of Earth’s volume and 32.5% of Earth’s Mass
3. Density is around 9.5 - 14.5 g/cm3
4. Two parts - Inner (solid) and Outer (liquid)
5. NiFe

Question 8

What does ‘Physical Properties’ refer to?

Answer 8

The physical properties of a layer refers to the properties of the layer which can be observed without changing its chemical composition, such as strength or rigidity.

Question 9

Based on the chemical composition, how many layers does earth have?

Answer 9

1. Lithosphere - parts of the upper mantle and crust (solid) - upper mantle
2. Asthenosphere - made of rock which has so much pressure it moves like liquid - upper mantle
3. Mesosphere - lower mantle
4. Outer core - barysphere refers to the core + whole interior of Earth
5. Inner core - barysphere refers to the core + whole interior of Earth

Question 10

Name the discontinuities between the layers of the Earth.

Answer 10

1. Conrad - hydrosphere and crust
2. Repetti - upper mantle and lower mantle
3. Mohorovic - crust and mantle
4. Guttenburg - mantle and core
5. Lehmann - outer core and inner core