Patterns of Crustal Activity

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1 Patterns of Crustal Activity Objectives Participants will: Identify the clues used by Alfred Wegener to piece together the continents (geologic, biologic, and glacial evidence) Locate & plot the location of common earthquakes & volcanoes as well as the world mountain ranges and how they relate to plate tectonics (convergent, divergent, and transform plate boundaries) Suggested Grade Levels 6 9 Subject Areas Earth Science Timeline minutes Standards D: Earth Science Background The history of plate tectonics - The mechanism behind plate tectonics - Source: Vocabulary Boundaries: convergent, divergent, transform. Students should have a firm grasp of longitude, latitude, and how to plot a coordinate point. Materials World maps that show mountain ranges on land and on the ocean floor (atlas, classroom map, etc.) Globes Earthquake location map* This could be a world map with earthquake locations plotted. Student texts might prove a useful source. Include earthquakes which have recently occurred. Another possibility (time permitting) is to have the students plot all of the earthquakes listed in the Appendix. *If this activity is being completed in association with a long-term earthquake-watch, the earthquake location map should be mounted on a corkboard with earthquake locations plotted using pins. An up-to-date listing of recent earthquakes and volcanoes can be obtained from the USGS, NEIC (National Earthquake Information Center) and several other sites on the Internet. Lesson 1. Students will see how scientific evidence was used to come up with the Theory of Continental Drift & Plate Tectonics. Students should be able to complete the procedure and independently arrive at the correlation between earthquakes, volcanism, and mountain building.

2 2. Follow-up discussion should relate the patterns of crustal activity identified in the lab to subduction zones, coastal mountain chains, oceanic trenches, and the difference in composition, thickness, and density between oceanic and continental crust. 3. Engagement: Groups of 2-3 students with each student having a blank piece of computer paper. Have each students rip the paper randomly into equally sized pieces and trade with another member of the group. Have them piece together the puzzle and ask them to identify the observations that were used and discuss how accurate their information is. Response: Shape only, moderately accurate) Repeat the same activity with a piece of lined paper. Clues this time are the shape, red/blue lines. Easier and more accurate. Repeat with a ¼ of a full sheet of newspaper. Clues are shape, pictures, words, graphics, etc. Easier and more accurate. 4. Exploration: Students will plot the location of earthquakes, volcanoes, and mountain ranges and look for a pattern of activity compared to a map of the plates of the crust (many available online) 5. Explanation: Students will be introduced to the concepts of convergent, divergent, and transform boundary zones and how they relate to the pattern of surface process (mountain building, volcanoes, trenches, etc.) Extensions Students can be given a random set of Earth continents randomly placed on the sheet so there are no clues given and have them piece together what they think Pangaea looked like. From there the teacher can provide geologic, biologic, and glacial data to give hints on how the continents were originally oriented. Evaluation/Assessment Responses to questions associated with the Earthquakes, Volcanoes, and Mountain Ranges plotting activity (attached below). Elaboration Evaluation: Have students make a journal entry based on the engagement explaining how they pieced the puzzle together, the clues they used, the ease, and the overall purpose of the activity. Note: It may be beneficial to have the students work as a group (2-3 students) on the map that is larger than 8½ x 11. It does work well having each student do their own map but it takes significantly longer. Additionally, it may give the students a better perspective if the map is cut out and taped/glued together in the shape of a column to see the whole globe. Resources The history of plate tectonics - The mechanism behind plate tectonics - Source:

3 Name Pd Date PATTERNS OF CRUSTAL ACTIVITY Introduction: Studies of tectonics have shown that crustal activities are occurring worldwide. Earthquakes, volcanoes, and mountain ranges do not occur randomly. There are special zones in which they occur. In this lab you will look for the relationships between locations of crustal activities. Objective: You will plot the areas in which earthquakes occur most frequently and identify crustal activities that appear related to these zones. Vocabulary: Mid-Atlantic Ridge Continental drift Plate tectonics - Procedure: 1. Plot the locations of earthquakes provided on the Earthquakes around the world on your map by placing an X in each area where the earthquakes have occurred. The dates are not important and do not need to be labeled on the map. 2. Do the same for the volcano chart except now use a small circle in the locations that they occur. 3. The map provided already has the major mountain ranges provided, however, you must include the mountains that are located underwater in the oceans. (Use the map in the back of the classroom on the wall. The dark purple areas are mountains.) 4. Using the chart, Active and Extinct Volcanoes Around World, plot and label the locations of the following volcanoes: Mauna Loa, Krakatau, Vesuvius, Mt. Rainer, Paricutin, Fuji, Mt. St. Helen s 5. Using the earthquakes around the world chart, plot the locations of the following earthquakes: January 30, 1998; August 20, 1998; August 17, 1999; October 16, 1999; December 7, 1999.

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6 Discussion Questions: (Be sure to use complete sentences.) 1) Your world map should show that earthquakes do not occur at random locations. Describe the pattern and location of earthquakes on your map. 2) How are the locations of earthquakes, mountain ranges, and volcanic activity related? 3) What regions of North and South America show the greatest crustal activity? 4) According to your map, what is the probability (the chances) of a major earthquake or volcano occurring? Are there any regions that are more likely to have these events occur? 5) Why do you think the perimeter around the Pacific Ocean referred to as the Ring of Fire? Conclusion: How do the patterns of earthquakes, volcanoes, and mountain ranges on Earth compare?