Discuss the major causes of earthquakes and famous “fault lines,” such as the San Andreas Fault in California. During your discussion, review the following terms:
earthquake
epicenter
fault
continental drift
magnitude
Richter scale
plate tectonics
plate boundary
seismicity
seismic
seismograph
Definitions can be found at the USGS’s Glossary of Seismology Terms: .
2.
Illustrate the concept of Earth’s fault lines in the following ways:
Squeeze a large sponge from either side and cause uplift in the middle.
Slide two sponges past each other and note how they do not slide easily, but rather stick together in places.
Use a large rubber band, draw a mark on it, and pull the ends to demonstrate stretching or thinning.
3.
Have students use butcher paper and a world map to create paper cutouts of the continents. Assemble the continents into a model of Pangaea, the supercontinent some scientists believe broke up beginning about 200 million years ago and drifted apart into what are now separate continents. Briefly describe the theory of plate tectonics and continental drift. (Continental drift theory, originally advanced by Alfred Wegener, postulates that Earth’s continents were originally one landmass. Pieces of the landmass split off and migrated to form the continents.) Compare the Pangaea model with the USGS animated globe showing plate boundaries at wwwneic.cr.usgs.gov/neis/plate_tectonics/plate_anim.html.
4.
Hand out copies of Map #1: Plates of the Earth, showing the boundaries of Earth’s tectonic plates.
5.
Explain to the class that it will be accessing and mapping information about the 10 largest earthquakes in the world in the 10 years from 1989 to 1998 and theorizing about the location of these earthquakes as they relate to Earth’s tectonic plates.
6.
Have students print a map of the Largest Earthquakes in the World in the Past Ten Years, available at the USGS’s National Earthquake Information Center Web site: wwwneic.cr.usgs.gov/neis/eqlists/last_big10.html.
7.
Students should examine the chart listing the location and magnitude of each quake and mark with a dot the locations of each earthquake on their Plates of the Earth map. Students should color-code their dots according to the magnitude of the quake. (After a brief discussion of the Richter magnitude scale, decide on a common color-coding system.)
8.
Have students discuss connections between what they have learned about plate tectonics and the data evidence on their maps. Were they surprised by the location of the 10 largest earthquakes? Did the location and magnitude of the earthquakes follow the edges of the Earth’s plates? Can they see any patterns in the locations of the earthquakes? (The teacher may want to use an overhead transparency of the Largest Earthquakes in the World map during discussion. Make sure all students understand how to read latitude and longitude degrees.)
Provide each student a copy of Map #2: World Map for Plotting Earthquakes. Explain that they will be charting earthquakes that occur for the next week, plotting the earthquakes on the map and color-coding their dots. (Use the same color-coding system used in step 7.)
11.
Each day for one week, have students visit the Near Real Time Earthquake List site and record the following information for each new earthquake. Groups may be assigned different parts of the world to map and record—such as near Japan or mainland United States, and so on. (Note: You may want to narrow the records to earthquakes with a magnitude of 5.0 or greater.)
Date/Time
Latitude
Longitude
Magnitude
General Location
12.
After students have collected this information each day, have them plot the earthquakes on their World Map for Plotting Earthquakes. After a week of entries, have students compare their World Map to Map #1: Plates of the Earth. Do they see any patterns? In what areas did most of the earthquakes occur?
13.
Next, have each group visit Web sites about earthquakes to find out how earthquakes occur and the possibilities for earthquake predictions along fault lines. Their data should support the theory that most earthquakes follow fault lines or Earth tectonic plate boundaries. Here are some Web sites with good earthquake information:
USGS Earthquakes Earthquake Shake Restless Planet: Earthquakes Understanding Earthquakes USGS: Plate Tectonics
14.
Have students present an oral report or a multimedia presentation on their one-week earthquake-tracking findings, along with information about how earthquakes occur and why they may occur along fault lines. If presentation programs, such as PowerPoint or HyperStudio, are used, the data maps may be scanned into the slides. The frequency or magnitude, or both, of a particular area’s earthquakes may be charted using a spreadsheet program and inserted into a presentation slide. The data can be used to support or refute current plate tectonic theory and earthquake predictions.
Focus on students’ current knowledge and experiences with earthquakes through the use of a “KWL” chart (What I Know; What I Want to Know; What I Have Learned). Encourage students to work in pairs as they enact the concept of a “fault” and assemble the plates of the Earth and continents into a model of Pangaea. As students access information about the Largest Earthquakes in the World, emphasize the concepts of latitude, longitude, and the Richter magnitude scale. A papier-mâché model of the Earth can be created in addition to a paper map. Discuss student predictions and compare earthquake patterns. A final project can focus on safety preparedness and procedures during an earthquake.
Based on your research, do you think that the theory of plate tectonics can help predict where earthquakes are going to occur? What is the value of being able to make such predictions?
2.
According to the theory of continental drift, about 200 million years ago, all the continents used to be part of one supercontinent. Over time, the supercontinent broke up and drifted apart—the separate pieces becoming the continents we know today. According to this theory, what might the Earth look like in about one million years? One hundred million years?
3.
Do you think there is any relationship between where earthquakes occur and where volcanoes erupt? Using your earthquake data, can you predict where volcanoes will occur?
4.
Imagine that you are a geologist called in to work on an international earthquake preparedness plan. What factors would you have to consider? What areas of the world would be targeted? What are the benefits of developing such a plan?
5.
Given the tremendous growth in technology, do you think there is a tool other than a seismograph that could be developed to measure the strength of an earthquake? Try your hand at designing such a device. How would it work? What would it measure? Is it more effective than a seismograph?
6.
Are you surprised at the number of earthquakes that occur on a regular basis? What do you think that the number of earthquakes tells us about the planet Earth?
Use this evaluation rubric, based on a three-point scale, to assess the group’s work in three areas: content, presentation format (written report or multimedia project), and oral presentation. In addition to completing a rubric as the teacher, you could ask the collaborative group and the audience (class) to complete one for the group as well. Total all three scores for a composite score.
THREE POINTS
A. Content:
Evidence of data and research information.
Depth in coverage of topic.
Explanations and reasons given for conclusions.
B. Presentation format (written report or multimedia project):
Written report shows evidence of correct grammar and spelling; a variety of sentence structures; paragraphs with main ideas and supporting details. Opening paragraph captures reader’s interest; supporting paragraph(s) offer research and data information; closing paragraph summarizes conclusions. Original data is listed in chart or graph form, or both. Research data and references are documented.
Multimedia presentation (PowerPoint, HyperStudio) shows evidence of clear organization; visual appeal through the use of large fonts (32 point or higher), graphics/pictures, and limited information on each slide; consistent use of noun or verb phrases for bulleted information; transitions between slides and text-body animation. Data is illustrated through graphs or charts, or both. Research data and references are documented.
C. Oral presentation:
Evidence of collaboration between group members.
Presentation well planned and coherent. Research information integrated with relevant personal experiences or real-world examples, or both.
Communication aids clear and useful.
TWO POINTS
Content includes data and research information, but not in depth. Data charts or graphs, or both, are included. Explanations and reasons for conclusions are limited or confusing. Presentation format demonstrates some organization but without compelling support for main ideas. Some research data and references are documented. Oral presentation shows evidence of group collaboration.
ONE POINT
Content includes very limited data and research information. Conclusions may not be relevant or present. Presentation format demonstrates a lack of organization and coherent support of ideas. Data is not presented in chart or graph form. Oral presentation shows little evidence of group members’ collaboration and contributions.
California’s Seismic Past
Students can learn more about California’s earth-shaking past and future
by viewing the Assignment Discovery program Fault Line: San
Francisco. Using the USGS site index, have students research
“Earthquake History: California.”
They can also learn more about the scientists who have made unique
contributions to seismology. A good starting point is “Men and
Women of Seismology” on the USGS site.
Faultlines
Have students compare a variety of magnitude scales, including the
Richter scale, used to measure the force of an earthquake. Ask them to
create a three-dimensional model illustrating plate tectonics theory,
continental drift, or fault lines, or a combination thereof.
Grade level: 9-12 Subject area: Earth and Space Science Standard:
Understands basic Earth processes. Benchmarks:
Understands the concept of plate tectonics (e.g., the outward transfer of the Earth’s internal heat and the action of gravitational forces on regions of different density drive convection circulation in the mantle; these convection currents propel the Earth’s crustal plates, which move very slowly, pressing against one another in some places and pulling apart in other places).
Grade level: 9-12 Subject area: Earth and Space Science Standard:
Understands basic Earth processes. Benchmarks:
Knows effects of the movement of crustal plates (e.g., earthquakes occur along boundaries between colliding plates, sea floor spreading occurs where plates are moving apart; mountain building occurs where plates are moving together; volcanic eruptions release pressure created by molten rock beneath the Earth’s surface).
Grade level: 6-8 Subject area: Earth and Space Science Standard:
Understands basic Earth processes. Benchmarks:
Knows that the Earth’s crust is divided into plates that move at extremely slow rates in response to movements in the mantle.
Barbara Linsley, Earth science online teacher for Discovery Channel School and technology trainer/teacher for Ontario-Montclair School District, Ontario, California.
