Color coded and labelled world earthquake map: Original USGS earthquake epicenters map with mid-ocean ridges in orange, volcanic zones in red, and tectonic plate boundaries outlined in blue. See This Dynamic Planet website to download an unlabelled original.
- Briefly review the patterns discovered by the students from the previous activity (The Big One).
- Pass out the volcano data strips and a single red color dot per student. Describe to them that their job is to read about their volcano and use the latitude and longitude information to plot the volcano on the map.
- One by one, have students come up to the front of the room to read the information about their volcano then plot their volcano on the map. While they plot their information, another student can come up and describe their volcano. Regulate the flow so that no more than 2-3 students are plotting their data on the map at one time.
- When all students have gone and all the data is plotted on the map, discuss any patterns you see on the map as a class. The goal here is have students recognize that volcanoes and earthquakes often line up along the same zones. Point out the ring of earthquakes and volcanoes that encircle the Pacific Ocean. This prominent zone is known as the “Ring of Fire”.
- Describe to students that there are many volcanoes under the ocean. Briefly discuss the discovery and characteristics of the mid-ocean ridges. If available, show the students photos or a video clip of the bizarre life forms near the ridges and thermal vents.
- Refer to the Mid-Ocean Ridges Map and place masking tape on the class map where the mid-ocean ridges are located. Point out how the mid-ocean ridges nearly encircle the globe in places (such as going almost all the way around Antarctica) and how they cross land masses in 2 places – Iceland and East Africa.
Trace and color code plate boundaries
- Give each student a World Earthquake Map.
- Distribute the colored pencils so each student has at least 3 different colors available.
- Place your overhead copy on the projector.
- Select one color to represent the mid-ocean ridges. Set up a legend in one corner of the map and create a key showing that that color represents mid-ocean ridges. Refer to the large class map and trace the mid-ocean ridges in that color.
- Select another color to represent volcanic zones. Add that color to your key. Refer to the large class map and trace the volcanic zones. Some volcanoes (Kilauea in Hawaii, Mount St Helens in Washington, Vesuvius, Etna and Stromboli in Italy, and Erta Ale in Africa) don’t appear to have others nearby. Use a single dot of color to represent them if so desired.
- Select another color to outline the plate boundaries. Connect the dots and lines to trace the boundaries of the major tectonic plates. If students overlook the Juan de Fuca, Scotia, and Arabian plates, that’s OK. Also, the boundary between the North American and Eurasian plates is difficult to identify. If students insist on placing it through Alaska based on the earthquake evidence rather than through Russia as it truly lies, don’t be surprised and use your judgment as to whether to let them proceed with that error or not.
- Finally, label each of the plates with the name of each plate. If you wish, label the “Ring of Fire” as well.
- Turn these maps in or store them in a safe place for use in future lessons (such as the Sea Floor Spreading activity).