Discovering Plate Boundaries has been selected for inclusion in the Reviewed Collection of the Digital Library for Earth System Education (DLESE)!

An article about Discovering Plate Boundaries was published in January 2005 in the Journal of Geoscience Education. Click to download the article.

Quick Start for DPB (much more info in Teachers Guide)

Materials needed:

1. Four 24" by 36" data maps mounted on the walls around the classroom
2. One B&W copy of the student instructions per student
3. Two B&W copies of the 11" by 17" Plate Boundary Map per student
4. One B&W overhead transparency of the 8.5" by 11" Plate Boundary Map per 4 students
5. Bucket of miscellaneous colored pencils
6. Several sets of non-permanent colored overhead transparency markers.
7. Set of slips of paper to use to assign each student to a Scientific Specialty and a Tectonic Plate

Note: Only items 2-4 are consumed during the exercise. The large data maps may be reused many times.

DPB is organized into three 50 minute periods. I will refer to these as Day 1, Day 2, and Day 3. However, the exercise may be done in one three hour lab period.

Day 1 Activity

When the students arrive for the first period of the class, I hand out the Student Instruction sheet, and a plate boundary map. I use 11 by 17 in black and white maps that I make on a copying machine. They are displayed at the same projection and base as the data maps, although to a smaller scale.

I also hand each student a slip of paper with a Scientific specialty (Seismology, Geochronology, Volcanology, or Geography) and a Plate Name (Pacific Plate, North American Plate, African Plate, and etc.). My goal is to have each student have a different combination of specialty and plate, and for all four scientific specialties to be covered for each plate used in the exercise. Therefore, if you have 24 students, I would use 6 plates and have all four specialties for each. Numbers that are not multiples of four can be handled by having 1-3 plates with only 3 specialties. If I have to do this, I drop a different specialty from each, but never Seismology. I bet you can guess that I am a Seismologist!
I mix the specialties and plates up randomly among students because I think this exercise works best if they are not self arranged into their usual social groupings.

I ask the students to assemble in their specialty groups at their respective maps: Seismologists at the Earthquake map, Volcanologists at the Volcano map, Geochronologists at the Seafloor Age map, and Geographers at the Topography map. Each group is asked to become familiar with their map. They should read the side label to see what is being displayed and how it is displayed. Some maps show locations of events. Other maps show contoured data using colors. They should work as a group to figure out what they are looking at. I find that at first those who dominate the discussion at the maps are the usual suspects. After a while, other leaders usually emerge, because they really begin looking carefully at the map and the data. I like watching this dynamic emerge!
While the students are doing this, I circulate among the groups listening and often clarifying misconceptions I hear popping up. I want to be sure that each group has reached an understanding of the basics of the data display. This usually takes about 15 minutes.

I then ask the students, still in their specialty groups at their maps, to begin to describe and classify their data. Each group is to work only with its data map. Each group is to come up with a classification of the plate boundaries of the world based on their data. They are to use up to 5 plate boundary type classifications. These are to be given numbers such as boundary type 1, boundary type 2, and etc. They are not to use plate tectonic terminology, although they will try! They are to write a description of how they identified their plate boundary types. I say that the description should be clear enough that someone unfamiliar with their map, and without help, could use their description to find examples of that boundary type on the map. They are then asked to use a colored pencil to mark (on their individual map) all plate boundaries in the world which fit that description. They should use different colored pencils for each of their boundary types.

I have the students keep their maps and Plate Boundary Type classifications after Day 1 to be used later in the exercise. I have them turn them in at the end of Day 3 of the exercise.

Day 2 Activity

When the students gather for Day 2 of the exercise, I ask them to assemble in their Plate Groups. Each plate group should consist of a seismologist, a volcanologist, a geographer, and a geochronologist. I usually have each group move to a lab table together. This will be a different group than they worked with the first day. I then explain that each group contains experts on all the data types, but that each expert has only looked at data in their own specialty area. Therefore each group needs to work their way around the maps to become familiar with all the data. As they stand at each map, the expert on that map should make an informal presentation to the others in their group about their data. They should first tell what the data are and how they are symbolized. They should then point out the most important features shown on their map. They should briefly introduce the plate boundary types they came up with and where they can be found in the world. They may want to pay particular attention to the boundary types they found at the boundaries of the plate their group is to work on. I then turn them loose on the maps.

As they seem to be finishing their presentations at the maps, about 15 minutes into the class, I get their attention to tell them that their next task is to come up with a new classification scheme for the boundaries of their plate (not the whole world). This scheme should be labeled Boundary type A, B, and etc, and should now be based on all four types of data. Thus a plate boundary type A might be described as having shallow earthquakes right on the plate boundary, sparse or no volcanoes, lying on a topographic high with deeper water to either side, and following a line of young seafloor. In most cases the students will do this by bringing together the classification maps they did the first day. They should notice that they plate boundary types that correlate (at least approximately) from data type to data type.

As they work on these new maps, which each student will have to make and turn in at the end of the exercise, I remind them to put their boundary type descriptions on the back of their new map and color the boundaries on the map. I also pass out the transparencies and markers and tell the students that a spokesperson from each plate group will need to speak to the class, using the marked up transparency, at the beginning of day 3.

Day 3 Activity

Day 3 of the exercise begins with the student group spokes-people making their presentations at the overhead projector. I generally ask them to describe their plate boundary classifications and then to give us a tour around their plate. Sometimes there are questions from other students; sometimes I ask questions to draw out some feature they have on their map, but have not talked about.

I lead the students in applause for each talk and thank the speaker. I also am sure to listen carefully to what they say as I try to repeat their observations when I am describing plate boundary processes later in the class.

I then spend the remainder of the class leading a discussion of plate boundary processes and introducing the terminology earth scientists use to describe these plate boundaries. I first use this graphic to discuss divergent boundaries, convergent (subducting) boundaries, and transform boundaries. I discuss why each of these boundaries have the particular observable phenomena the students have seen. I try to frequently refer to words that they used in their presentations to describe these.

I have a set of transparencies that show close-ups of the Discovering Plate Boundaries data maps for particularly good examples of each type of plate boundary. These are very handy for illustrating the data relationships that characterize each fundamental type of plate boundary. Each map in the transparency covers exactly the same area, making comparison easy.

I try to let the students lead me in directions of their interest. There are usually many questions about what is going on at various plate boundaries, and sometimes away from plate boundaries (ie. Hawaii!). This type of discussion inevitably finishes off the third day of the exercise and may extend into the next day of the class.

I have the students turn in their 2 annotated plate boundary maps as they leave. I usually grade these in a very simplified way. I give them a zero, check minus, check, or check plus for each map. Check minus reflects very little or careless work on the map. Check plus reflects an above average product relative to the age and ability of the students.

Thats the quick version. Please remember that there is much more information to be found in the Discovering Plate Boundaries Teachers Guide!