THE EARTH'S INTERIOR TEST QUESTION

Directions:

A. Choose the letter of the correct answer.

For questions 1 and 2, refer to the figure below that shows the cross section of the Earth as seismic waves travel through it.

1.  An S-wave shadow zone is formed as seismic waves travel through the Earth’s body. Which of the following statements does this S-wave shadow zone indicate?

a. The inner core is liquid.

b. The inner core is solid.

c.  The mantle is solid.

d. The outer core is liquid.

2.  Why are there no P-waves or S-waves received in the P-wave shadow zone?

a.  P-waves are absorbed and S-waves are refracted by Earth’s outer core.

b.  P-waves are refracted and S-waves are absorbed by Earth’s outer core.

c.  Both the P-waves and S-waves are refracted by Earth’s outer core.

d.  Both the P-waves and S-waves are absorbed by Earth’s outer core.

3.  What makes up the lithosphere?

a.  Continental crust

b.  Crust and the upper mantle

c.  Oceanic crust and continental crust

d.  Upper mantle

4.  Miners dig into the Earth in search for precious rocks and minerals. In which layer is the deepest explorations made by miners?

a.  Crust                                             c. Mantle

b.  Inner core                                    d. Outer core

5.  How do you compare the densities of the Earth’s crust, mantle, and core?

a.  The mantle is less dense than the core but denser than the crust.

b.  The mantle is less dense than both the core and the crust.

c.  The mantle is denser than the core but less dense than the crust.

d.  The mantle is denser than both the core and the crust.

6.  The movement of the lithospheric plates is facilitated by a soft, weak and plastic-like layer. Which of the following layers is described in the statement?

a.  Asthenosphere                           c. Lithosphere

b.  Atmosphere                                d. Mantle

7.  Alfred Wegener is a German scientist who hypothesized that the Earth was once made up of a single large landmass called Pangaea. Which of the following theories did Wegener propose?

a.  Continental Drift Theory

b.  Continental Shift Theory

c.  Plate Tectonics

d.  Seafloor Spreading Theory

8.  If you are a cartographer, what will give you an idea that the continents were once joined?

a.  Ocean depth

b.  Position of the south pole

c.  Shape of the continents

d.  Size of the Atlantic Ocean

9. Which observation was NOT instrumental in formulating the hypothesis of seafloor spreading?

a.  Depth of the ocean

b.  Identifying the location of glacial deposits

c.  Magnetization of the oceanic crust

d.  Thickness of seafloor sediments

10. As a new seafloor is formed at the mid-ocean ridge, the old seafloor farthest from the ridge is destroyed. Which of the stated processes describes how the oceanic crust plunges into the Earth and destroyed at the mantle?

a.  Convection

b.  Construction

c.  Diversion

d.  Subduction

11.  In 1912, Alfred Wegener proposed a theory that the Earth is once a single landmass. What is the name of the Mesozoic super continent that consisted of all of the present continents?

a.  Eurasia

b.  Laurasia

c.  Pangaea

d.  Gondwanaland

12. Who were the two scientists who proposed the theory of seafloorspreading in the early 1960s?

a.  Charles Darwin and James Hutton

b.  Harry Hess and Robert Dietz

c.  John Butler and Arthur Smite

d.  F. Vine and D. Mathews

13.  Which of the following diagrams best illustrates the convection occurring in the mantle?

14.  During the 1960s, scientists were already equipped with gadgets needed to explore the deep ocean. What discovery about the ocean floor is associated with the seafloor spreading?

a.  Mountains are denser than the mantle.

b.  The rotational poles of the Earth have migrated.

c.  The crust of the continents is more dense than the crust of the ocean.

d.  The crust of the ocean is very young relative to the age of the crust of the continents.

15.  If the Atlantic Ocean is widening at a rate of 3 cm per year, how far (in kilometers) will it spread in a million years?

a.  3 kilometers

b.  30 kilometers

c.  300 kilometers

d.  3000 kilometers

16.  Which of the following increases with distance from a mid-ocean ridge?

a.  the age of oceanic lithosphere

b.  the thickness of the lithosphere

c.  the depth to the sea floor

d.  all of the above

17.  Which of the following can you infer from the continuous movement of the lithospheric plates over the asthenosphere?

a.  All the continents will cease to exist.

b.  All the volcanoes in the Philippines will become inactive.

c.  The continents will not be located in the same place as they are now.

d.  The islands of the Philippines will become scattered all over the world.

18.  If all the inner layers of the Earth are firm solid, what could have happened to Pangaea?

a.  It remained as a supercontinent.

b.  It would have become as it is today.

c.  It would have slowly disappeared in the ocean.

d.  It would have stretched and covered the whole world.

19.  Why does the oceanic crust sink beneath the continental crust at the subduction zone?

a.  The oceanic crust has a greater density.

b.  The oceanic crust is pulled downward by Earth’s magnetic field.

c.  The oceanic crust is pushed from the ridge.

d.  The continental crust has a denser composition.

10. The lithospheric plates are believed to be moving slowly. What is the driving force that facilitates this movement?

a.  gravitational force of the moon

b.  magnetic force at the poles

c.  convection current in the mantle

d.  the force of the atmosphere

B. Answer briefly the following questions.

1.  What are the different layers of the Earth?

2.  Why is there a need to study the Earth’s layers?

3.  What proves the existence of the boundary between the crust and the mantle?

4.  What are the characteristics of the asthenosphere?

5.  What do the shapes of the continents now tell us about their past?

C. Complete the concept map below about continental drift, seafloor spreading, and plate tectonics.