Unit 2.1: Recognizing plate boundaries
Summary
Students work individually to make observations about the distribution of earthquakes, volcanoes, topography, and the age of the sea floor from four maps, then work in small groups to synthesize their observations and characterize plate boundaries.
Learning Objectives
At the end of the unit, students will be able to:
- Use patterns in topography, earthquake distribution, and volcano distribution to infer the location and character of tectonic plate boundaries.
Context for Use
This activity is intended for use at the beginning of an introductory Earth Science course for college-level students. The activity could be used with any class size, and can be completed in one 75-minute class period, plus additional time for pre-class and homework assignments.
The activities could be expanded to take place during two 75 minute classes if the activity is run as a jigsaw or gallery tour rather than an instructor-guided discussion.
Students will need colored pencils or crayons in class.
Description and Teaching Materials
Teaching Materials:
- Pre-class assignment (Microsoft Word 2007 (.docx) 1.7MB Sep10 24) (making observations about maps)
- Maps used in pre-class assignment and in-class activity
- 11x17 inch versions:
- Earthquakes (Acrobat (PDF) 8.2MB Sep7 24)
- Active volcanoes (Acrobat (PDF) 7.3MB Sep7 24)
- Topography (Acrobat (PDF) 13.9MB Sep7 24)
- Age of the crust (Acrobat (PDF) 9.6MB Sep7 24)
- Poster-sized versions (if choosing to run the activity as a jigsaw or gallery tour):
- Earthquakes poster-size (Acrobat (PDF) 3.2MB Jan15 23)
- Active volcanoes poster-size (Acrobat (PDF) 2.2MB Jan15 23)
- Topography poster-size (Acrobat (PDF) 58.3MB Jan15 23)
- Age of the crust poster-size (Acrobat (PDF) 5.5MB Jan15 23)
- 11x17 inch versions:
- Slides to guide class activity (PowerPoint 2007 (.pptx) 6.3MB Sep10 24)
- Short version of student handout for in-class activity (Microsoft Word 2007 (.docx) 2.5MB Sep10 24) (synthesis of data at two example plate boundaries)
- Long version of student handout for in-class activity (Microsoft Word 2007 (.docx) 2.4MB Sep10 24) (synthesis of data at four example plate boundaries)
- (can be used for both long and short versions of the activity)
- Post-class homework assignment (Microsoft Word 2007 (.docx) 1.7MB Sep10 24) (reading about plate tectonics)
The instructor will need to:
- Make copies of the student activity handout, one for each student
- Print 11x17 inch paper copies of each map (Pre-class assignment map files) or have students bring laptops or tablets to class to view the maps electronically. If using paper copies, print at least two of each map per group of 3–4 students, or print one set of maps for each student. If running the activity as a gallery tour or jigsaw (alternate version, see Teaching Notes and Tips below), only one poster-sized copy of each map will be needed for classes with fewer than 20 students. For larger classes, additional copies will be needed so that there is one for each gallery tour circuit.
- Bring colored pencils or crayons for students to borrow, and/or ask students to bring their own.
Pre-class assignment:
Students look at four maps (earthquakes, volcanoes, topography, and age of sea floor) and make observations about the data shown on each map. These observations will be shared with peers during the in-class activity.
In class:
Part 1: Students share observations about maps (45 min)
- Students form small groups (3-4 students) and share observations about each map that they made during the pre-class assignment. The class slides are set up to have students discuss each map with their group and report out their ideas to the whole class. This will allow the instructor to ensure that key observations about each map are being recorded. In addition to students recording their observations in the activity handout, the instructor may use the blank slides in the slide deck to record observations or record observations on a whiteboard or poster paper.
- There are many alternate ways to run this activity, including allowing students to work through the observations at their own pace, creating a jigsaw with students becoming experts with one data set and then combining ideas to examine specific plate boundaries, or creating a gallery tour where students can record observations as a class.
Part 2: Students synthesize their observations (20 min)
- Students continue working in their groups to synthesize their observations from all maps to describe characteristics of plate boundaries.
- The student handout contains prompts to describe the data patterns at either two plate boundaries (short version; Mid-Atlantic ridge, Peru-Chile trench) or four plate boundaries (long version; Mid-Atlantic ridge, Peru-Chile trench, India-Asia convergence, Pacific-N. America transform), depending on how much time you have available.
- It is unlikely that students will be able to synthesize the data at all four example plate boundaries in 20 minutes. We recommend using the short version (two plate boundaries) unless the class has more time (e.g., during a lab period or splitting the activity to run over the course of two 60-75 minute class periods). Focusing on the differences between these two plate boundary types can form the foundation for later discussions about additional plate boundary types.
Part 3: Reflection (10 min)
- Leave 10 minutes at the end of class for students to complete the reflection questions at the end of the student handout.
- Alternatively, these questions could be discussed as a class, or assigned for homework.
Homework:
Students read/watch the following to review plate tectonic theory and answer questions (see homework file in teaching materials above):
- Read Visionlearning: Origins of plate tectonic theory
- Read Visionlearning: Plate boundaries
- Read Visionlearning: Earth Structure
- Watch this YouTube video about plate tectonics and the drivers of plate motions.
Teaching Notes and Tips
Rather than having students work in small groups and progressing through the maps as a class, this activity could be run as a gallery tour with poster-sized versions of each map, or as a jigsaw, with students becoming experts on one data type and then combining their knowledge to examine specific plate boundaries. My experience is that students have difficulty making the key map-scale observations of each data type and sometimes focus on small-scale observations at specific locations. Progressing through the activity together as a class is one strategy to make sure that students are making the key observations that will help them to classify plate boundaries.
Assessment
LO1: Use patterns in topography, earthquake distribution, and volcano distribution to infer the location and character of tectonic plate boundaries.
- In-class activity, student handout, and class discussion
References and Resources
Egger, A.E. (2003). Earth Structure. Visionlearning Vol. EAS(1).
Egger, A.E. (2003). Origins of Plate Tectonic Theory. Visionlearning Vol. EAS-1(1)
Egger, A.E. (2003). Plate Boundaries. Visionlearning Vol. EAS(2).
Hasterok, D., Halpin, J. A., Collins, A. S., Hand, M., Kreemer, C., Gard, M. G., & Glorie, S. (2022). New Maps of Global Geological Provinces and Tectonic Plates. Earth-Science Reviews, 231, 104069. https://doi.org/10.1016/J.EARSCIREV.2022.104069
IRIS (2022) New!! What Drives Plate Tectonics? What Are the Forces Involved? (new convection ending; 2022) YouTube, 10 Jan. 2022, https://www.youtube.com/watch?v=hUtYyRUBdZQ
Sawyer, D.S., Henning, A.T., Ship, S., Dunbar, R.W. (2005). A data rich exercise for discovering plate boundary processes. Journal of Geoscience Education, 53(1), 65-74.