Download Activity EarthBeneath 150209

The Earth Beneath Our Feet
Name/Date/Period
You will visit a series of stations, following the directions at each station. Do the stations in any
order and write your answers on this paper. After visiting the stations, you will synthesize the information
from each station into an ACE paragraph that will explain a major theory called plate tectonics.
STATION A --- Ages and Patterns
For the questions below, please use the years on the Timeline Handout that correspond to the time
periods listed on the key to the Geologic Map. For example on the Geologic Map, the light blue color by
A in the Pacific or Atlantic Ocean is Pliocene (shown on the Ocean Geology Key). Then look up Pliocene
on the Timeline Handout, and you see Pliocene rocks are 1.6 to 5.3 million years old.
1) What is the age range of the rocks in the oceans? Use both ages and time period names.
2) Look at both the Geologic Map and the Plate Map. What feature on the Plate Map corresponds to the
youngest oceanic rocks on the Geologic Map?
3) What is the age range of the rocks on the continents? Use both ages and time period names.
STATION B --- The Hot-n-Cold Boogie
Watch the demonstration of the cold milk being poured into the hot tea. Make sure one of you watches the
top of the beaker and that the other one watches the sides of the beaker.
1) Draw two sketches: one of what you saw from the top of the beaker and one of what you saw from the
bottom of the beaker.
(plan view of
top of beaker)
(crossof beaker)
section view
2) Go back to your sketches and add words to describe what happened to the cold milk from the time it
first was poured into the beaker of hot tea, and then what it did when it hit the bottom of the beaker.
3) What you just saw and described is a process called convection. The mantle is partially liquid and acts
similarly to the cold milk in the hot tea. Use the cold milk in the hot tea as a model to describe what
happens when cold asthenosphere (the cold milk) sinks into warm mantle (hot tea) and then hits the
bottom of the mantle (bottom of the beaker).
STATION C --- A Geopuzzle
From the folder at Station C, put the pieces together like you would a jigsaw puzzle. The
landmass that you just re-created is called Pangaea, the super-continent. It formed about 350 million
years ago, and began to break up about 250 million years ago. When done, please put the pieces back into
the baggies.
1) Since the break-up of Pangaea, what feature has developed between Europe and North America?
2) List three things that were used as evidence that Pangaea existed. These are things that are the same
from the edge of one continent across to another continent when Pangaea is assembled.
STATION D --- Good-bye, California
Use both the Plate Map and Volcanoes and Earthquake Map to answer the following questions.
1) Along what feature on the Plate Map do the majority of both earthquakes and volcanoes occur?
2) What type of plate boundary has relatively more earthquakes and volcanoes?
3) Based on your observations above, why are people in California nervously awaiting the “Big One”?
4) If you were to advise people in Los Angeles where to move to get away from earthquakes, would you
suggest the east coast of South America or the east coast of Japan? Explain in complete sentences
(CS).
STATION E --- It’s a Piece of Cake
You will be using food to model convergent plate boundaries and divergent plate boundaries.
Get 1 piece each of brownie and cake per person. AFTER you are done with Station E, you can eat the
cake and brownie.
1) The brownie represents oceanic crust (the type of crust that is under the oceans). The cake represents
continental crust (the type of crust that makes up the continents). Both of these types of crust are on
most of the plates. Which type of crust is denser? thicker? Make a quick sketch of the brownie and
cake, but label them oceanic crust and continental crust.
2) Place one of the pieces of cake on one side of the paper towel, and one of the brownie pieces on the
other side. Have one partner keep the paper towel flat, and the other partner moves the cake and
brownie toward each other until they collide, and keep pushing them together after they first collide.
Draw a quick sketch of the brownie and cake, but label them oceanic crust and continental crust.
Based on the definitions of the words converge and diverge, have you created a convergent or
divergent plate boundary? Explain (CS).
3) The process you just modeled and drew in #2 is called subduction. Write a definition for subduction
using your answer to #2.
4) Place one of the pieces of cake on one side of the paper towel desktop, and the other piece of cake on
the other side. One partner keeps the paper towel flat, and the other moves them toward each other
until they collide, and keep pushing them together after they first collide. Draw a quick sketch. Based
on the definitions of converge and diverge, have you created a convergent or divergent plate
boundary? Explain (CS).
5) Place the two pieces of brownie narrow end to narrow end. Pull them apart slightly. Draw a quick
sketch, showing the brownies and the paper towel between the brownies. Label the brownies oceanic
crust and label the paper towel gap as asthenosphere. Have you created a convergent or divergent
plate boundary? Explain (CS).
6) The type of plate boundary you created in #5, a ____________ plate boundary, is also called a
spreading zone. In real life, magma from the asthenosphere will fill in the “hole” created when the
plates pull apart and new crust is created. What type of crust is created? (HINT: what type of crust
does the brownie represent?) Are most of the divergent plate boundaries located in the oceans or on
continents?
STATION F --- The Future World
Answer the following questions using the Future Map of the World and the Plate Map. The light
brown areas surrounding the continents on the Future Map of the World are continental shelf areas,
considered to be part of the continents. On this same map, the darkest areas are the locations of the
continents today, while the lighter continents are the positions that the continents will occupy on 50
million years.
1) What happened to the Nazca Plate? (Use the terminology from the brownie under the cake, Station E.)
2) Which of the following oceans have become bigger? smaller? remained the same? (Look at the
Atlantic Ocean, Pacific Ocean, and Indian Ocean.)
3) Look at the symbol for diverging plate boundary. Would you expect that Africa (or part of it) might
eventually become separated from Asia? Explain (CS).
Putting It All Together
Answer the following questions.
1) What is the surface of the earth broken into? And what geologic processes are common at their edges?
(Station D)
2) Compare the ages of the rocks in the oceans to the ages of rocks on the continents. (Station A)
3) How did we know that the continents on the Earth were once joined together in a single land mass?
(Station C)
4) What mechanism might account for the moving plates? Where does this process occur? (Station B)
5) What are the two major types of plate boundaries you learned about? There is a third major type of
plate boundary in which plates slide past each other, called a transform plate boundary. (Station E)
Conclusion Essay
In science, theories must be accompanied by supporting evidence. As a group, we will go over this essay
and write part of it together. Follow the the rubric attached. Use all the vocabulary words in bold type on
this paper.
Type and double-space your essay. Each person must hand in a separate essay, but you may work
together in class if there is time.