Materials Included In Kit

Additional Materials Required

Safety Precautions

Although materials in this activity are considered nonhazardous, follow all normal laboratory safety procedures. Remind students to exercise care when using scissors to cut out the puzzle pieces.

Lab Hints

• Make a copy of one of the puzzle pages to use as a master sheet for doing this activity with additional classes.
• Laminating the physiographic charts provided in the kit will allow you to not only conserve and preserve the charts, but students would also be able to plot the data points on the chart using washable fine point markers, like overhead pens. The charts can then be reused simply by wiping them off with a damp paper towel.
• Providing rulers for the students to use in plotting the map coordinates—one ruler for the latitude and the other for longitude—will keep them from straying too far from the actual location.

Teacher Tips

• The earthquake and volcano data lists provided with the kit are for your convenience. If current data is desired, finding updates is easy by accessing the following websites: http://earthquake.usgs.gov/ (Accessed June 2018) http://volcano.oregonstate.edu (Accessed June 2018) http://www.volcano.si.edu/ (Accessed June 2018)
• Instruct students that when plotting earthquake and volcano locations from the lists provided that latitude is designated N or S, meaning north or south of the Equator. Longitude is designated E or W, meaning east or west of the prime meridian. Note: All longitude numbers with a W (west) label will be found between 0° and 180° (the International Date Line) on the center right portion of the physiographic chart. Students may want to label East and West on their charts.
• A discussion of earthquake magnitude, measured by the Richter scale, may be of interest to students. Magnitude is determined by seismographic data and is a measure of the strength or strain energy released by an earthquake. The values on the Richter scale (see Table 1 in the Teacher PDF), as originally defined by Charles Richter (1935), are logarithmic in nature. This means that an earthquake measuring 5.6 on the Richter scale releases seismic waves that are 10X higher than the seismic waves released from a 4.6 quake. This 10-fold increase in wave height (amplitude) translates into a 30-fold increase in the amount of energy released. Another way of looking at this is: A quake of 6.6 releases 900X (30 x 30) the energy of a 4.6 quake, therefore, it would take 900 earthquakes with a magnitude of 4.6 to equal the energy released from one 6.6 earthquake! Events with magnitudes of about 4.5 or greater are strong enough to be recorded by seismographs all over the world. Table 1 contains Richter magnitudes combined with the Modified Mercalli Intensity scale (see next Tip).
• Earthquake intensity may be discussed using the Modified Mercalli scale. Intensity is a way to measure the effects of an earthquake on humans, structures or the land itself at a specific place. The intensity depends upon the earthquake’s magnitude, the distance to the epicenter and the local geology, since certain soil types or terrain can amplify the effects. The Mercalli scale is used by engineers to help them design and construct buildings within earthquake-prone areas. The scale contains 12 levels of quake intensity, written with Roman numerals.

Further Extensions

Alignment with AP^® Environmental Science Topics and Scoring Components

Topic: Earth Systems and Resources. Earth Science Concepts (Geologic time scale, plate tectonics, earthquakes, volcanism; seasons; solar intensity and latitude).
Scoring Component: 1-Earth Systems, Land.

Answers to Prelab Questions

1. How is the theory of plate tectonics related to earthquake and volcanic activity?

   The movements of the tectonic plates build up pressure along the boundaries. When this pressure is released, an earthquake or volcanic eruption occurs or both.

2. Why is the study of earthquakes and volcanoes important?

   As our understanding of the underlying forces that cause earthquakes and volcanoes increases, so will our ability to save lives and to limit damage to property.

Sample Data

Part 1

The following diagram illustrates the way the puzzle pieces should be put together.

Answers to Questions

1. Look carefully at the marked physiographic ocean chart. Are the locations of earthquakes and volcanoes randomly scattered over the Earth or do they seem to be more concentrated in certain areas? Explain your answer. Student answers will vary but should include that earthquakes and volcanic activity are concentrated in certain areas.
2. Which area of the world had the most volcanic activity according to the data provided? Most volcanic activity occurs along the west coast of the Americas and along the eastern portion of Asia.
3. Which area of the world had the most earthquake activity according to the data provided? More earthquakes seem to occur around the Pacific Ocean.
4. The physiographic chart shows many geologic features of the ocean floor. Write the names of the major geologic features of the ocean floor that are located at or very near the location of the earthquakes and volcanoes that were plotted (i.e., basins, ridges, rises, trenches). Student answers will vary but may include features, such as trenches, fracture zones, rises, ridges, seamounts, abyssal plains, basins.
5. Look carefully at the marked chart and assembled puzzle. If the edges of each crustal plate “puzzle” piece represent crustal plate boundaries, describe the relationship between the location of volcanoes and earthquakes and the boundaries of the crustal plates. Be specific. Most earthquakes and volcanoes are located very near crustal plate boundaries.

6. Look carefully at the marked chart and a textbook, if necessary, to answer Questions 6a and 6b.
   1. Which geologic feature(s) of the ocean floor do you think have been formed by crustal plates moving together?

      When two plates are coming together (converging), a subduction zone and trench are created when the heavier plate overrides a lighter plate and pushes it down into the mantle.

   2. Which geologic feature(s) of the ocean floor do you think have been formed by crustal plates moving apart?

      Two crustal plates are forced apart (diverging) as magma from the mantle is forced up into the fissures and cracks of the crust by pressure. When the magma hits the cold sea water, it solidifies until another buildup of pressure from the mantle cracks open the crust again. Ridges and seamounts are formed this way.

7. Obtain a copy of the table containing the combined Richter and Modified Mercalli Scales. Use the table, the Earthquake Data List, the physiographic chart, and the assembled puzzle to answer the following questions.
   1. According to the Mercalli Scale, how many of the earthquakes listed would have been felt by all people in the area?

      All the earthquakes on the list have a magnitude over 4.0, therefore they all would have been felt by all the people.

   2. According to the data, how many of the earthquakes would be described as moderate?

      On the Richter scale, moderate earthquakes have a magnitude of 5.0–5.9. Therefore, 20 earthquakes from the list are moderate.

   3. Which tectonic plates were involved in producing the strongest earthquake listed?

      The Australian and Eurasian plates were involved in producing the earthquake in the Banda Sea.

Teacher Handouts

12792_Teacher1.pdf

Introduction

Mother Nature’s most spectacular phenomena, earthquakes, volcanic eruptions and their associated effects, make headline news whenever and wherever they occur. Are these two singular events related? Are earthquakes and erupting volcanoes more likely to occur in certain areas of the world than in others? Find answers to these important questions as you map the locations of such events around the world.

Concepts

• Map plotting—latitude/longitude
• Theory of plate tectonics

Background

For centuries, earthquakes and volcanoes have both fascinated and frightened. In ancient times, Poseidon, the “god of the sea” of Greek mythology was believed to possess the power of “earth-shaker” and Vulcan, the Roman god of fire and the forge, was thought to be “busy working” when volcanic eruptions occurred. Seismologists and volcanologists, those who study earthquakes and volcanoes, respectively, have provided us with more credible scientific explanations for these awesome displays of Nature’s power. Unfortunately, however, our ability to predict when and where they will occur is still not an exact science. Without warning, on December 26, 2004, an undersea earthquake off the northern coast of Sumatra, Indonesia triggered a tsunami that killed more people than any tsunami in recorded history—at least 283,100 with an additional 14,100 unaccounted for and missing.

As our understanding of the underlying forces that cause earthquakes and volcanoes increases, so will our ability to save lives. We now know that one indication of impending volcanic eruptions is a cluster of imperceptible-to-human earthquakes. The invention of the seismograph in 1880 made it possible to detect these small earthquakes and also to measure the velocity of earthquake waves. As early as 1872, a scientist determined that earthquakes usually occur along fault lines. After the San Francisco earthquake of 1906, another scientist proposed that earthquakes result when built-up pressure along fault lines is suddenly released.

In 1910, a German meteorologist and astronomer named Alfred Wegener (1880–1930) published a book describing a theory he called Plate Tectonics. The essentials of the theory are:

• The lithosphere—the “crust” of the Earth—is composed of several massive plates.
• These plates sit atop the Earth’s semi-solid mantle and as the magma (molten rock) within the mantle slowly moves, the overriding plates of the crust move with it.
• The movements of the plates build up pressure along the edges or boundaries of two plates. When the pressure is released, an earthquake and/or volcanic eruption occurs.

Experiment Overview

The purpose of this activity is to increase understanding of the Theory of Plate Tectonics and visualize how it is used to explain earthquake and volcano locations. This will be done by assembling a puzzle of the Earth’s major tectonic plates then plotting and analyzing the location of a list of earthquakes and volcanic eruptions that have occurred around the world.

Materials

Prelab Questions

1. How is the theory of plate tectonics related to earthquake and volcanic activity?
2. Why is the study of earthquakes and volcanoes important?

Safety Precautions

Although materials in this activity are considered nonhazardous, please follow all normal laboratory safety procedures. Exercise care when using scissors to cut out the puzzle pieces.

Procedure

Part 1

1. Work with a partner throughout the entire activity. Obtain one sheet of puzzle pieces and a physiographic chart of the ocean floor from the instructor.
2. Cut out and correctly arrange the puzzle pieces on top of the physiographic chart. Note: The correctly arranged pieces will cover all of the chart except the portion from 0° to 30° E.
3. Have the instructor check to ensure that all the pieces are placed correctly. Upon approval, use clear tape to attach all the pieces together. Note: Do not attach the puzzle to the physiographic chart.

1. Obtain a copy of the Earthquake Data List and two rulers.
2. Plot the location of 45 earthquakes from the list onto the physiographic chart using the latitude and longitude numbers. Use one color of a colored pencil or marker to show the location of each earthquake by making a small circle or dot. The rulers will help in plotting the locations more precisely.
3. Obtain a Volcano Data List and plot the location of the 45 volcanoes using the latitude and longitude numbers. Use a colored pencil or marker of a different color to show the location of each volcano by making a small circle or dot.
4. In the lower left corner of the chart, make a legend indicating which colors represent earthquakes versus volcanoes.

Student Worksheet PDF

12792_Student1.pdf