Download Interactive Dynamic Earth ANSWERS

Name______________________________Teacher___________Period_______Date_________
Type in the following website to your browser, or go to
the Class Links on my webpage to access it.
http://www.learner.org/interactives/dynamicearth/
If you don’t finish today and need to restart in the middle of this tomorrow, go to the green bar
across the top of the page to choose the chapter on which you stopped.
Read the intro and click on “Start your exploration with Earth's Structure.” Roll your mouse over
each layer and answer the questions below.
1. Starting from the center, list the layers inside the Earth. Core (inner, outer), Mantle (mesosphere,
aesthenosphere, lithosphere) Crust
750 mi/ 1200 km
2. How wide is the inner core?
Iron and nickel
3. What two elements make up the inner core?
1400 mi/ 2300 km
4. How wide is the outer core?
The only liquid layer 5. How is the outer core different from other layers?
Asthenosphere
lithosphere?
6. Which layer that we haven’t studied yet is directly underneath the
Plates
7. The lithosphere is divided up into what slow moving objects?
20 mi/ 30 km
8. What is the average thickness of the crust under the continents?
Click on “Next Chapter: Plate Tectonics.” Follow the directions given on the page, then click on
“How Do We Know This” and answer the following questions.
Alfred Wegener
theory?
9. Whose observations & theories became the basis for the plate tectonics
Pangaea
10. What did he call the one large landmass?
200 million years ago11. How long ago did Pangaea begin to break up?
65 million
12. How many years ago did Madagascar separate from Africa?
135 million
13. How many years ago did the Indian landmass separate from the AntarcticaAustralia landmass?
40-50 million
1960’s
accepted?
14. How many years ago did Greenland separate from North America?
15. During what decade did the theory of plate tectonics become widely
Name______________________________Teacher___________Period_______Date_________
Click on “Continents Over Time” and follow the directions given there. This will lead you to
click on “Plate Boundaries” when you are finished.
Slow_____________ 16a. The theory states that the plates are in constant, ___ motion.
15
16. According to this website, how many major tectonic plates are there?
Oceanic crust
17. What type of crust is found under the oceans?
Continental
18. Which type of crust is thickest, continental crust or oceanic crust?
Continental
19. Which type of crust is oldest, continental crust or oceanic crust?
Landmasses
20. All the plates have names, usually referring to ___, oceans, or regions of the
globe where they are located.
Boundary
21. The border between two tectonic plates is called a _______.
3
22. How many different main types of plate boundaries are there?
Divergent
23. A ___ boundary marks two plates that are moving apart.
Transform
24. A ___ boundary occurs where two plates slide past one another.
Convergent
25. A ___ boundary occurs where two plates are pushing toward each other.
Divergent
26. The boundary between the African plate and the Arabian plate in the Red
Sea is an example of a ___ boundary.
Transform
27. The boundary between the Pacific plate and the North American plate in
California is an example of a ___ boundary.
Convergent
28. The boundary that occurs along the western coast of South America is an
example of a ___ boundary.
Name______________________________Teacher___________Period_______Date_________
Use the map at the bottom of the screen to see where the three different types of plate boundaries
are found throughout the world. First, find the KEY in the green box located in the lower righthand corner of the map. Then, roll your mouse over each boundary name in the KEY to see its
location. Answer the following questions.
Divergent
29. Between the North American plate and the Eurasian plate going through
Iceland is mostly a ___ boundary.
Transform
30. Between the North American plate and the Caribbean plate is a ___ boundary.
Convergent
31. Between the Phillipine plate and the Pacific plate is a ___ boundary.
Click on “Plates and Boundaries Challenge” and follow the directions given. Only play the Plates
and Boundaries Challenge once and then move onto the next chapter titled “Slip, Slide and
Collide.”
Movements
32. Each kind of plate boundary is associated with particular events, so if you
know about the ___ taking place at a plate boundary, you can often predict what's likely to occur there
— volcanoes, earthquakes, mountains, trenches — in the future!
Click on “See What Happens at Different Plate Boundaries.”
Convergent Boundaries – Colliding Plates
Oceanic
33. The events that occur at convergent boundaries are linked to the types of
plates, ___ or continental, that are interacting.
Oceanic
34. Which plate is pulled underneath the other when oceanic and continental
plates collide? (This is called “subduction.”)
Trench or Valley
35*. As the oceanic crust sinks, a ___ is formed at the edge of the continent.
Roll your mouse over each name to review layers of the Earth and the subduction zone.
Ring of Fire
Ocean?
36. What is the name of the active volcanic region that encircles the Pacific
Older
the other one.
37. When two oceanic plates collide with one another, the ___ one sinks below
Island arcs
38* This leads to the creation of __________ __________.
Aleutian
Alaska.
39. An example of island arcs that are produced from this are the ___ Islands in
Earthquakes
40*. This kind of collision often causes ___ which can result in tsunamis.
200,000
41. How many people were killed in Asia due to a tsunami like this in 2004?
Name______________________________Teacher___________Period_______Date_________
Mountains
42*. Most often, a collision between two continental plates crunches and folds
the rock at the boundary, lifting it up and leading to the formation of ___.
Roll your mouse over each name to review layers of the Earth and mountains.
Himalaya
43. The ___ Mountains contain the tallest mountain peaks on Earth.
40-50 million years ago 44. When did the Himalayan mountain range begin to form?
Taller
45. Are the Himalaya Mountains getting taller or shrinking in size?
Divergent Boundaries – Spreading Plates
Seafloor
___ spreading.
46. Divergent plates pulling apart from one another in the ocean contribute to
Mid-ocean ridge 47* As plates made of oceanic crust pull apart, a crack in the ocean floor appears.
Magma then oozes up from the mantle to fill in the space between the plates, forming a raised ridge
called a __- ___ ____.
Rift valley
48*. What is formed when two continental plates diverge?
Lakes
may form.
49. After the rift occurs, valleys form, volcanoes are more active, narrow ___
Click on Start to see an animation of this.
Transform Boundaries – Grinding Plates
Horizontal
boundaries?
50. In which direction are plates moving past each other at transform
Fault
51. What is formed as a result of this type of movement?
Earthquakes
52.Transform boundaries and the resulting faults produce many ______ because
edges of tectonic plates are jagged rather than smooth.
Stress
53. What is built up along this fault and then released as an earthquake?
Strike- slip fault
54. What type of fault is the San Andreas fault?
1989
55. According to the website, when was the most recent “major event” along
this fault?
Click on “Plate Interactions Challenge.” Participate in the challenges as directed on the screen.
After this, you will be finished for the day.