Introduction
We have been learning about earthquakes this week so today and tomorrow you will be completing a Webquest.
The teacher askes the class "has anyone ever been in an earthquake?" before allowing the students to go to the computers for the webquest.
Task
Your task is to complete the WebQuest questions by using this website: http://www.nationalgeographic.org/interactive/forces-nature.
Write your answers down on a piece of paper.
When you are done with the Webquest give it to me for a grade. Don't forget to put your name on it and number your paper!
You have the whole class today and tomorrow to complete the Webquest.
Process
To start: go to the website, start Flashplayer, chose earthquakes, on the upper left menu, choose number 1 to read about earthquakes.
Answer the following questions on a sheet of paper:
1. When do earthquakes happen?
2. How many earthquakes occur every day? Each year?
3. Where and what year was the deadliest quake ever? How many people were killed?
Next, On the upper left menu, choose number 2. Read “Where Do Earthquakes Occur?”.
Answer:
4. Where do most earthquakes occur?
5. What are the earthquakes called that are far from plate boundaries and why do they occur?
6. What percentage of earthquakes comes from the largest earthquake belt?
Next, On the upper left menu, choose number 3. Read “What Causes Earthquakes?”
Answer:
7. What is “plate tectonics”?
8. In which state is the San Andreas Fault?
9. How long is the San Andreas Fault?
10. How deep is the fault?
11. How many earthquakes occur along this fault each year?
Next, On the upper left menu, choose number 4. Read “Types of Faults”
12. List the four (4) types of faults
13. Click on “Normal Fault” Why do normal faults occur?
14. Draw a picture of a normal fault.
15. Click on “Next fault type” How does a reverse fault occur?
16. Draw a picture of a reverse fault.
17. Click on “Next fault type” How does a strike-slip fault occur?
18. Draw a picture of a strike-slip fault.
19. Click on “Next fault type” Why do dip-slip faults occur?
Next, On the upper left menu, choose number 5. Read “Measurement and Recording”.
Answer:
20. What is the “hypocenter?”
21. What is the point directly above the hypocenter?
22. Click “Next” What is another name for a P wave?
23. Click “Next” What instrument measures seismic waves?
24. What does a Richter Scale measure?
Next, On the upper left menu, choose number 6. Read “Locate an earthquake?”.
Answer:
25. What do you need to pinpoint the epicenter of an earthquake?
Click “Trigger an Earthquake” Watch the three (3) seismograph recordings.
Click on each triangle.
Click on the point where all three (3) circles intersect.
26. Write down the Location, Latitude, Longitude, and Magnitude information about the earthquake you triggered.
Next, On the upper left menu, choose number 7 Read “Trigger an earthquake”. 1. Select a ground type. 2. Select a magnitude. Click on “Start the earthquake” Play again until you think you have created the biggest earthquake.
Answer:
27. What type of ground causes the most destruction? Would a low magnitude or a high magnitude cause a bigger earthquake?
Next, On the top-right menu, click on Map. Locate the 1906 San Francisco earthquake and click on it. Write down the Magnitude, deaths, date, and damage of the earthquake. Then, Play the video at the bottom.
Answer:
28. Compare San Francisco before and after the earthquake and give three details to support your comparison.
Evaluation
The teacher grades the papers as they turn them in.
Here are the answers:
1. When do earthquakes happen? Earthquakes happen when plates, or rocks, within the Earth suddenly break or shift under stress, sending shock waves rippling.
2. How many earthquakes occur every day? Each year? Thousands of earthquakes occur every day and about 500,000 quakes occur each year.
3. Where and what year was the deadliest quake ever? How many people were killed? The deadliest quake ever occurred in China in 1557, when an estimated 830,000 people were killed.
4. Where do most earthquakes occur? Most earthquakes occur along with fractures in the Earth’s crust called faults. These are found along the edges of major plates.
5. What are the earthquakes called that are far from plate boundaries and why do they occur? Earthquakes that occur far from plate boundaries are called intraplate quakes. They occur when stress builds up and the Earth’s crust is stretched or squeezed together until it rips.
6. What percentage of earthquakes comes from the largest earthquake belt? 80%
7. What is “plate tectonics”? Plate tectonics is the phenomenon that the Earth’s plates are constantly moving and interacting with each other - they push against each other, pull apart, or grind past one another.
8. In which state is the San Andreas Fault? California
9. How long is the San Andreas Fault? More than 800 miles (1,290 kilometers)
10. How deep is the fault? It is at least 10 miles (16 kilometers) deep.
11. How many earthquakes occur along this fault each year? Thousands.
12. List the four (4) types of faults: 1. Normal Fault 2. Reverse Fault 3. Strike-Slip Fault 4. Dip-Slip Fault.
13. Click on “Normal Fault” Why do normal faults occur? Normal faults occur what plate boundaries pull apart and Earth’s crust is stretched. One side of the fault slips down.
14. Draw a picture of a normal fault.
15. Click on “Next fault type” How does a reverse fault occur? A reverse fault (also known as a thrust fault) occurs where plates are colliding and one side of the fault is pushed up and over the other.
16. Draw a picture of a reverse fault.
17. Click on “Next fault type” How does a strike-slip fault occur? In a strike-slip fault, the plates meet evenly and slide against each other horizontally.
18. Draw a picture of a strike-slip fault.
19. Click on “Next fault type” Why do dip-slip faults occur? Dip-slip faults are strike-slip faults combined with either a normal fault or a thrust fault. One plate moves sideways, and one moves downward.
20. What is the “hypocenter?” The hypocenter is the place where the movement first occurred in the fault. It can be hundreds of miles below the Earth’s surface or just beneath it.
21. What is the point directly above the hypocenter? The point directly above the hypocenter is called the epicenter.
22. Click “Next” What is another name for a P wave? Primary wave
23. Click “Next” What instrument measures seismic waves? Seismograph
24. What does a Richter Scale measure? The magnitude of the quake.
25. What do you need to pinpoint the epicenter of an earthquake? You need the seismic wave measurements from three recording stations. Around each station, you draw a circle with a radius equal to its distance from the quake. The epicenter is where all three circles intersect.
26. Write down the Location, Latitude, Longitude, and Magnitude information about the earthquake you triggered. Location: San Francisco, Latitude: 37.04 N, Longitude: 121.88 W, Magnitude: 7.1
27. What type of ground causes the most destruction? Would a low magnitude or a high magnitude cause a bigger earthquake? landfill; high
28. Compare San Francisco before and after the earthquake and give three details to support your comparison. Date: April 18, 1906, Magnitude: 7.8, Deaths: 700 - 3000, Damage: 28,000 buildings destroyed. When comparing and explain the rest of this answer; the student's answers will vary.
Conclusion
The class comes back together for one final class discussion about what they learned in the Webquest. Students are also allowed to tell the teacher what they like about the Webquest and what they would like to do differently with the next webquest.