❇️1Q W3 | Formative Assessment #1: Earth's Internal Structure

Question 1

The Gutenberg discontinuity lies at the boundary of what two layers?
- Mantle and outer core

• Outer Core and Inner Core
• Mantle and innercore
• Upper Mantle and Lower Mantle

Answer 1

Mantle and outer core

Question 2

The boundary between the mantle and the core lies at a depth of approximately ________.
- 1000 kilometers

• 300 kilometers
• 3000 kilometers
• 5000 kilometers

Answer 2

3000 kilometers

Question 3

Match each layer of the earth’s interior with its thickness.
Continental Crust -
Oceanic Crust -
Mantle -
Outer Core -
Inner Core -

Answer 3

Continental Crust - 40 Km
Oceanic Crust - 5 Km
Mantle - 2885 Km
Outer Core - 2270 Km
Inner Core - 1216 Km

Question 4

________ is the least rigid sometimes described as plastic in nature.
- Lithosphere

• Centrosphere
• Mesosphere
• Asthenosphere

Answer 4

Asthenosphere

Question 5

The inner core of the Earth is made up of _____________________.
- nickel-iron alloy

• iron
• silicon and oxygen
• copper

Answer 5

iron

Question 6

Which of the following statements is true?
- The lithosphere contains the crust and the upper mantle.

• The crust contains the lithosphere.
• The lithosphere and crust are different terms for the same part of the Earth.
• The lithosphere and crust are totally separate parts of the Earth.

Answer 6

• The lithosphere contains the crust and the upper mantle.

Question 7

What property distinguishes BEST the earth’s crust, mantle, and core?
- Composition

• State (solid vs. liquid)
• Pressure
• Temperature

Answer 7

Composition

Question 8

Temperature of ______ ranges from 3000
- Core

• Lava
• Magma
• Mantle

Answer 8

Core

Question 9

The Moho is the boundary between _________________.
- the lithosphere and the asthenosphere

• the inner core and the outer core.
• the crust and the mantle.
• the mantle and the core.

Answer 9

the crust and the mantle.

Question 10

The oceanic crust consists mainly of _________.
- basaltic rocks

• granitic rocks
• ultramafic rocks
• gabbroic rocks

Answer 10

basaltic rocks

Question 11

How do we know that Earth is not the same composition all the way through?
- Seismic waves do not arrive uniformly all over the earth.

• There are two types of seismic waves, S- and P-waves.
• Where the mantle is exposed, it looks very different.
• Seismic waves attenuate with distance.

Answer 11

Seismic waves do not arrive uniformly all over the earth.

Question 12

What conclusion can you make about the density of Earth layers from the diagram?
- As temperature and pressure increase density increases.

• Temperature and pressure are unrelated to density
• Pressure and temperature are the only factors controlling density
• As temperature and pressure increase, density decreases.

Answer 12

As temperature and pressure increase density increases.

Question 13

______ is the densest of all layers.
- The core

• Mesosphere
• Centrosphere
• Crust

Answer 13

The core

Question 14

The continental crust is ______________________ than oceanic crust.
- thicker and less dense

• thicker and more dense
• thinner and less dense
• thinner and more dense

Answer 14

thicker and less dense

Question 15

What is the correct order of Earth’s Physical/Mechanical Layers?
- lithosphere, asthenosphere, mesosphere, outer core, inner core

• lithosphere, mesosphere, asthenosphere, outer core, inner core
• asthenosphere, lithosphere, mesosphere, inner core, outer core
• mesosphere, lithosphere, asthenosphere, lithosphere, outer core, inner core

Answer 15

lithosphere, asthenosphere, mesosphere, outer core, inner core

Question 16

Earthquakes are useful for studying Earth’s interior because ________________.
- each earthquake produces an array of seismic waves

• earthquakes are extremely destructive
• they happen below the surface of the Earth
• they release stress that has been stored

Answer 16

each earthquake produces an array of seismic waves

Question 17

Both S-waves and P-waves can travel easily through liquids.
- True
- False

Answer 17

False

Question 18

As seismic waves penetrate deep into the earth, through which layers do they slow down rather than speed up?
- Asthenosphere and outer core

• Asthenosphere and lithosphere
• Lithosphere and mesosphere

-

Answer 18

Asthenosphere and outer core
“The asthenosphere and outer core, being partially liquid and fully liquid, respectively, slow down seismic waves (or block them entirely).”

Question 19

What does the S-wave shadow zone indicate about Earth’s interior?
- The core is made of iron.

• The mantle is denser than the crust.
• The mantle is liquid.
• The outer core is liquid.

Answer 19

The mantle is liquid.

Question 20

Which of the following statements regarding the inner core is true?
- P waves do not travel through the inner core.

• Primary S waves (those generated at the focus of an event) travel through the inner core.
• P waves travel through the inner core at a higher velocity than S waves travel through the inner core.
• the inner core is thought to be a liquid.

Answer 20

P waves travel through the inner core at a higher velocity than S waves travel through the inner core.