Introduction to Earth Science

Introduction to Earth Science

Quiz 7 - Earth's Structure and Plate Tectonics

1) The rigid outer part of the earth, consisting of the crust and upper mantle. is a relatively cool, rigid shell and averages about 100 km in thickness and called the:
a. asthenosphere
b. lithosphere
c. stratosphere
d. cryosphere

2) What is a magnetic field reversal?
a.  when Earth's magnetic field suddenly disappears for short periods of time
b. when Earth's magnetic field suddenly runs east/west instead of south/north 
c. when Earth's magnetic field leaves the south pole and enters the north pole
d. when Earth's magnetic field leaves the north pole and enters the south pole 

3) The alignment of iron-rich minerals in old volcanic lava flows show that:
a. the Earth's magnetic poles may have moved.
b. the Earth's magnetic poles have switched alignment many times in the past.
d. the continents have moved over time.
e. all of the above.

4) The first to arrive at a distant location from an earthquake is:
a. a shear (S) wave.
b. a compression (P) wave.
c. a sound (S) wave.
d. a rupture.
e. none of the above.

Questions 5-13 apply to the Structure of the Earth Diagram below. Note layers on left are classified by chemical properties, right are physical properties.
Structure of the Earth diagram
Match letters (A to J) to features on the Structure of the Earth diagram.
5) Which letter is the Asthenosphere?
6) Which letter is the Atmosphere?
7) Which letter is the Inner Core?
8) Which letter is the Crust?
9) Which letter is the Lithosphere?
10) Which letter is the Mantle?
11) Which letter is the Mesosphere?
12) Which letter is the Oceans?
13) Which letter is the Outer Core?

14) The Mohorovicic discontinuity (or Moho) is:
a. the boundary between granitic continental crust and basaltic oceanic crust.
b. the boundary surface between the earth's crust and the mantle, lying at a depth of about 6–7 miles (10–12 km) under the ocean bed and about 24–30 miles (40–50 km) under the continents.
c. the boundary between earth’s rigid mantle and the liquid core.
d. a fault boundary between two plates in a subduction zone.

15) Isostacy allows continental crust rises above sea level because it is:
a. denser than ocean crust.
b. is mostly basalt in composition compared with ocean crust.
c. contains more granitic rocks than ocean crust.
d. all of the above.

16) This extensive region that surrounds the Pacific Ocean basin is both a major earthquake zone and volcano zone.
a. Ring of Volcanoes
b. Ring of Fire
c. Pacific Island Arc
d. The Marianas Trench

17) The theory of continental drift (proposed by Alfred Wegener in 1912) was supported by what kind of evidence?
a. matching fossils on different continents
b. shapes of continents appear to fit like a jigsaw puzzle
c. matching rocks and mountain ranges on different continents
d. all of the above

18) The most conclusive proof for continental drift was provided by:
a. the coastlines of continents on a world map.
b. evidence of sea-floor spreading.
c. identical fossils and rocks found on two separate continents.
d. changes in climatic patterns.

19) The supercontinent in the continental drift hypothesis was called:
a. Panthalassa.
b. Pangaea.
c. Africana.
d. Pandora.

20) Geologic mapping shows that bedrock on all continental landmasses around the world range in ages that are exceeding old. However, the oldest rocks found in the world’s ocean basins are:
a. about 2 million years.
b. about 20 million years.
c. about 200 million years.
d. about 2 billion years.
e. none of the above.

21) Mid-oceanic ridges are sites with active volcanism, mild earthquakes, and,
a. thin sediment cover because ocean floor is being newly formed.
b. basaltic composition.
c. locations of hot water vents on the seafloor.
d. all of the above.

22) The theory of plate tectonics helps explain the location of volcanoes and earthquakes. Which of these also describes the current theory of plate tectonics?
a. it combines elements of continental drift and seafloor spreading.
b. it suggests that the lithosphere is divided into pieces, called plates.
c. denser ocean crust sinks below less-dense continental crust along subduction zones.
d. all of the above.

23) A mid-ocean ridge is an example of what type of plate boundary?
a. convergent zone
b. divergent zone
c. transform zone
d. subduction zone

24) The youngest rocks on the ocean floor are typically located near what feature?
a. a mid-ocean ridge
b. a subduction zone
c. an island arc
d. a deep-sea trench

25) A rift valley is evidence of which kind of plate boundary?
a. convergent
b. transform
c. divergent
d. uniform

26) What happens when an oceanic plate converges with a continental plate?
a. The denser oceanic plate slides on top of the less dense continental plate.
b. The denser oceanic plate slides under the less dense continental plate.
c. The less dense oceanic plate slides past the denser continental plate.
d. The less dense oceanic plate slides under the denser continental plate.

27) At what type of plate boundary are most continental mountains formed?
a. convergent
b. hotspots
c. divergent
d. transform
e. mid-ocean ridges

28) What kind of movement created the Himalayan Mountains?
a. convergence of oceanic crust with continental crust.
b. divergence between two continental crustal plates.
c. transform movement between oceanic and continental crustal plates.
d. convergence of two plates composed of continental crust.

29) According to the theory of plate tectonics:
a. the asthenosphere is divided into plates.
b. the lithosphere is divided into plates.
c. the asthenosphere moves over the lithosphere.
d. the asthenosphere is strong and rigid.
e. all of the above.

30) In plate tectonics theory, a plate can be made up of:
a. continental lithosphere only.
b. oceanic lithosphere only.
c. both continental and oceanic lithosphere.
d. both continental and oceanic asthenosphere.

31) What kind of plate boundary occurs where two plates grind past each other without destroying or producing lithosphere?
a. divergent boundary
b. transitional boundary
c. convergent boundary
d. transform boundary

32) What type of boundary occurs where two plates move together, causing one plate to descend into the mantle beneath the other plate?
a. transform fault boundary
b. convergent boundary
c. divergent boundary
d. transitional boundary

33) Deep ocean trenches are associated with:
a. ocean ridge systems.
b. transform fault boundaries.
c. subduction zones.
d. rift zones.

14) The Hawaiian Islands are associated with what type of volcanism?
a. intra-plate volcanism at a hot spot
b. subduction zone volcanism
c. volcanism at a divergent plate boundary
d. volcanism at a convergent plate boundary

35) Almost all deep-focus earthquake occur along or near what type of plate boundary?
a. convergent
b. passive
c. transform
d. divergent

36) Which type of plate boundary is in the southern California region?
a. passive
b. divergent
c. convergent
d. transform

37) Rift valleys, like the Great African Rift Valley, form as a result of:
a. crustal compression.
b. crustal extension.
c. stress and strain.
d. ductile deformation.

Questions 38 to 40 are related to the Plate Boundary Map below.
Plate tectonics map of the world

38) According to the Plate Boundary Map, what type of plate boundary occurs between the North American Plate and the Eurasian Plate?
a. transform boundary
b. divergent boundary
c. convergent oceanic-continental plate boundary
d. convergent oceanic-oceanic plate boundary

39) According to the Plate Boundary Map, what type of boundary occurs between the South American Plate and the Nazca Plate?
a. transform boundary
b. convergent continental-continental plate boundary
c. a convergent oceanic-continental plate boundary
d. convergent oceanic-oceanic plate boundary.

40) According to the Plate Boundary Map, Which of the seven major lithospheric plates consists mostly of oceanic lithosphere?
a. Pacific Plate
b. Antarctic Plate
c. Indo-Australian Plate
d. South American Plate