Big Idea 6: Earth Structures - Plate Tectonics (CS1)

Big Idea 6: Earth Structures

The Theory of Plate Tectonics (CS1)

Big Idea 6: Earth Structures

Over geologic time, internal and external sources of energy have continuously altered the features of Earth by means of both constructive and destructive forces. All life, including human civilization, is dependent on Earth's internal and external energy and material resources.

Explore the scientific theory of plate tectonics by describing how the movement of Earth's crustal plates causes both slow and rapid changes in Earth's surface, including volcanic eruptions, earthquakes, and mountain building. (SC.7.E.6.5 - DoK 2)

• The Earth's crust is broken into pieces that are called plates. These plates sit on the solid, but flowing rock of the mantle, which causes them to shift. There are two types of crust/plates, continental (makes up continents) and oceanic crust (makes up ocean floor).

• Mantle rock flows because heat from the core transfers to the bottom layer of the mantle, which makes the rock less dense so it flows toward the crust. When away from the hot core, the mantle rock cools and sinks back down toward the core, creating circular convection currents within mantle rock.

• The convection currents in mantle rock are what causes plate tectonics, or the shifting and interactions of tectonic plates.

• There are three types of interactions between the boundaries of two plates. The plates may move toward each other (convergent boundary), move away from each other (divergent boundary), or slide parallel past one another (tranform boundary).

Explore the scientific theory of plate tectonics by describing how the movement of Earth's crustal plates causes both slow and rapid changes in Earth's surface, including volcanic eruptions, earthquakes, and mountain building. (SC.7.E.6.5 - DoK 2)

• At a convergent boundary, the plates can push against each other, forcing the earth upwards, creating a mountain range or one plate can subduct or slide underneath the other creating deep ocean trenches or volcanic mountain ranges.

• At a divergent boundary, two plate move apart, creating a mid ocean ridge or a rift valley.

• At a transform boundary, plates slide past each other, their friction causing breaks, or faults, in the rock. The moving rock can sometimes get stuck, gathering energy and resulting in an earthquake.

Multiple Choice

The diagram shows the boundary of two tectonic plates and a feature that forms on Earth's surface at that boundary. At which of the following plate boundaries does the feature shown in the diagram form?

• a continental plate and an oceanic plate sliding past each other

• a continental plate subducting beneath an oceanic plate

• two oceanic plates moving away from each other

• two oceanic plates moving toward each other

Multiple Choice

The interaction of Earth's plates at plate boundaries causes changes to Earth's surface. The diagram shows a plate boundary and features of Earth's surface.

Which of the following features formed as a result of the plate interactions shown in the diagram?

• folded mountains

• mid-ocean ridge

• rift valley

• volcanic islands

Multiple Choice

A scientist finds a fossil of a fern in a hot, dry desert. The fern is the ancestor of a modern fern that lives in warm, moist climates. Which of the following is the best conclusion for the scientist to draw?

• The desert was underwater in the distant past.

• Ancient ferns were able to live in very dry climates.

• The climate of the desert has stayed the same over time.

• The desert had a warm, moist climate in the distant past.

Multiple Choice

Interactions between layers of Earth cause convection currents to move crustal plates. The diagram shows four layers of Earth. In which layer of Earth are the convection currents that directly result in tectonic plate motion found?

• 1

• 2

• 3

• 4

Multiple Choice

Ravi learns that convection currents within the mantle cause tectonic activity on Earth’s surface. What happens in a convection current?

• heated material sinks and cooler material rises

• heated material rises and cooler material sinks

• rock material melts and moves toward the Earth’s core

• rock material hardens and becomes part of Earth’s mantle

Multiple Choice

The movement of tectonic plates can produce landforms on Earth’s surface. Along what type of plate boundary might a mountain range form?

• transform only

• divergent only

• both convergent and divergent

• both transform and divergent

Multiple Choice

Earth’s tectonic plates move very slowly. Which of the following causes the movement of Earth’s tectonic plates?

• magnetic pole reversal

• large faults in mountain ranges

• energy released from volcanic activity

• convection of Earth’s upper mantle

Multiple Choice

Earth’s lithospheric plates meet at locations called plate boundaries. What happens at a transform boundary?

• the plates move away from each other

• the plates do not move

• the plates move toward each other

• the plates slide past each other

Multiple Choice

The table shows a listing of states that have earthquakes, the number of earthquakes greater than 3.5 on the Richter scale, and the percent of the total number of earthquakes this state had compared to other states between 1974 and 2003. Based upon this data, what conclusions can be drawn as to the region of the United States that has the most divergent plate boundaries that cause earthquakes?

• The east coast has the most divergent plate boundaries, because it had the fewest number of earthquakes.

• The midwest has the greatest amount of divergent plate boundaries, because it had more earthquakes than the east coast.

• The west coast has more divergent boundaries than the rest of the country, because it had the most number of earthquakes.

• The east coast has the most divergent plate boundaries, because Connecticut and Florida had earthquakes greater than 3.5 on the Richter scale.

Multiple Choice

Why are there no large mountains in Florida?

• Florida is close to sea level.

• Florida is close to the ocean.

• Florida is far from the Prime Meridian.

• Florida is far from major tectonic plate boundaries.

Multiple Choice

The diagram shows the movement of two of Earth’s plates. The plates are pulling apart. What can MOST likely be found just beneath these plates?

• Earth’s core

• hot, melted rock

• lava and ash

• another set of plates

Multiple Choice

The diagram shows a cross-section of the lithosphere. Point C represents a boundary between two tectonic plates. The plates shifted in opposite directions. What occurred at Point A as a result of this movement?

• a release of energy that caused an earthquake

• the formation of a tsunami, or underwater seismic wave

• the formation of a hot spot

• the sinking of one plate under another

Multiple Choice

Tectonic activity can recycle old crust and form new crust in different places. Where on the ocean basin would you expect to find new oceanic crust?

• along a trench because two plates slide past one another

• along an abyssal plain because two plates collide

• long a subduction zone because one plate sinks beneath another

• along a mid-ocean ridge because two plates pull apart

Multiple Choice

Imagine a metamorphic rock that has been subjected to intense heat and pressure. Over time, it gets pulled underground with a tectonic plate that is sinking beneath another plate along a convergent boundary. The rock melts as it goes deeper; then the molten rock rises up and seeps out of a crack in the ocean floor and hardens. What type of rock is it now?

• composite

• igneous

• metamorphic

• sedimentary

Multiple Choice

Earth’s mantle plays an important role in plate tectonics. Why is the mantle so important to this process?

• Earthquakes occur constantly in the mantle, which causes the plates to move.

• The mantle is made up entirely of liquid rock, on which Earth’s crustal plates can float.

• Heavy metals in the mantle set up strong magnetic fields that attract and repel Earth’s plates.

• Temperature differences in the mantle set up convection currents that help to drive the movement of the plates.

Multiple Choice

An earthquake occurs when rock in Earth's crust breaks or slips, quickly releasing pressure. In which location is an earthquake least likely to occur?

• in the middle of a plate

• at a boundary where plates pull apart

• at a boundary where plates push together

• at a boundary where plates slide past each other

Multiple Choice

The Marianas Trench, where the Pacific Plate descends under the leading edge of the Eurasian Plate, is the deepest sea floor in the world. These ocean trenches form when two oceanic plates collide

• and the older, less dense of the two plates rides over the edge of the older plate.

• when convection currents in the mantle force the older plate downward.

• and the younger, denser of the two plates, rides over the edge of the older plate.

• and the plates are approximately the same age and density.

Multiple Choice

Where would sea floor spreading most likely occur?

• At convergent boundaries (oceanic vs. oceanic)

• At convergent boundaries (oceanic vs. continental)

• At divergent plate boundaries (oceanic vs. oceanic)

• At transform plate boundaries

Multiple Choice

The image shows the Pacific Ring of Fire, a region of high tectonic activity. What evidence supports the theory that the tectonic activity of the region is due to the subduction of tectonic plates?

• The region is bound by many oceanic trenches.
• North America seems to be colliding with Asia at the north of the ring.
• The Asia-Pacific region is dotted by many small and large islands
• The landmasses look like they would fit together like the pieces of a jigsaw puzzle.
  

Multiple Choice

What geological forces might be responsible for this range of mountains?

• diverging tectonic plates
• erosion of the land by the ocean
• converging tectonic plates
• deposition of sediments by the ocean
  

Multiple Choice

The map in the picture shows tectonic plate boundaries. This map would be useful in predicting the location of future

• droughts

• hurricanes

• earthquakes

• tornadoes

Multiple Choice

Observe this diagram of a plate boundary. One statement BEST describes what is happening. It is that

• the oceanic crust is melting.

• the denser ceanic crust is subducting under the less dense oceanic crust

• volcanic islands are forming.

• the tectonic plates are moving away from each other.

Multiple Choice

Subduction zones occur on Earth where dense oceanic crust dives under more buoyant continental crust. These boundaries are characterized by a deep ocean trench next to a high continental mountain range, large numbers of earthquakes and volcanoes. All of this is further evidence for the

• big bang theory.
• theory of plate tectonics.
• origin of the species.
• theory of natural selection.
  

Multiple Choice

What occurs when two plates come together and the denser one is forced under back into the mantle?

• reduction

• conduction

• subduction

• convection

Multiple Choice

A divergent boundary occurs when plates ....

• Pull apart

• Come together

• Slide past each other

• subducting

Multiple Choice

The type of plate boundary where two plates come together is a .....

• Convergent Boundary

• Divergent Boundary

• Transform Boundary

• Plate Boundary

Multiple Choice

Which of the following causes Earth's tectonic plates to move?

• Energy from the Sun

• Magnetic Pole Reversal

• Convection currents in the mantle

• Faults in Mountain Ranges

Multiple Choice

The San Andréa fault in California is one example of a...

• Divergent boundary

• Convergent boundary

• Transform boundary

• All of the above

Multiple Choice

The mechanism that moves continents is based on heat energy moving by

• Radiation in the core

• Conduction in the lithosphere

• Convection in the Asthenosphere

• None of these options is true

Multiple Choice

What type of features are associated with a divergent boundary?

• Rift valleys

• Volcanic mountains

• Fold mountains

• Fault block mountains

Multiple Choice

The Himalayan mountains have some of the highest peaks like Mt. Everest, on which type of convergent boundary are they located?

• Oceanic/Continental

• Oceanic/Oceanic

• Continental/Continental

• None of the above

Multiple Choice

Where are most divergent boundaries located?

• Along the middle of most ocean floors

• Along the margins of most continents

• Across the middle of many continents

• All the above options are correct

Multiple Choice

Evaluating the relationship between scientific laws, theories, and hypothesis, one can say

• Scientific hypothesis can became laws

• Scientific theories can became laws

• Scientific laws can be changed

• Scientific hypothesis can became theories

Multiple Choice

The rejection of Mr. Wegener's hypothesis teaches us that

• Indirect evidence is not sufficient to prove a hypothesis

• Direct evidence is hard to find

• Hypotheses are hard to prove

• Scientists of the early 1900s were not smart enough

Multiple Choice

Peer scientists reviewing Wegener’s hypothesis of continental drift rejected his notion because

• His evidence was too few to make a valid conclusion

• He did not explain how continents move and what moves them

• His evidence was not clear in showing how continents were joined

• He lied by including false evidence

Multiple Choice

Wegener suggested that coal beds discovered in Antarctica indicated that this continent was

• once under water

• always frozen

• once near the equator

• part of Africa

Multiple Choice

Evidence used by Wegener to supported his idea of continental drift included

• Ocean rocks and sediments

• Ocean floor topography

• Magnetic isochron patterns

• Climatic data

Multiple Choice

A German scientist Alfred Wegener was the first to hypothesize that ...........

• Continents were once joined

• The sea floor is spreading

• Continents are moving

• The Earth's magnetic pole flips

Multiple Choice

Pangaea was an ancient supercontinent made up of...

• America, Greenland, and Europe.

• Antarctica, India, and America.

• all of Earth’s continents.

• South Africa, India, Australia, and South America.