The Plate Tectonics Revolution

Emily Peterman

Bowdoin College
a
Private four-year institution, primarily undergraduate
.

Summary

Although only ~40 years old, the theory of plate tectonics provides a global framework to understand such varied phenomena as earthquakes, volcanoes, ocean basins and mountain systems both on continents (e.g. the Himalaya, the Andes) and beneath the seas (e.g. the East Pacific Rise, the Mid-Atlantic Ridge). In-depth analysis of plate boundaries, the driving forces of plate tectonics, global plate reconstructions and the predictive power of plate tectonics.

Course URL:
Course Size:

less than 15

Course Context:

This is an upper-division course in plate tectonics. The prerequisite for this course is one intro-level course. Given that the department is Earth and Oceanographic Science, the intro course could be Intro to Oceanography, Environmental Geology and Hydrology or Investigating Earth (101). Lectures and three hours of laboratory or field trip per week. Two-day (weekend) field trip is required. 100% of the students in this course are majors.

Course Goals:

Students should be able to explain the emergence of the theory of plate tectonics as a result of the scientific method
Students should be able to associate geologic hazards/features with different types of plate boundaries
Students should be able to explain the geologic evolution of Eastern and Western North America through the lens of plate tectonics
Students should be able to describe the tectonic history of their individually assigned plate
Students should be able to construct a 4-D timeline of their plate that starts in 500 Myr, extends through the present and projects into the future.
Students should be able to postulate what the earth will look like in 15 Ma, 50 Ma and 100 Ma by relying upon evidence from the current configuration of plates and their present motion (as well as changes in relative plate motion)
Considering the regions that are particularly active tectonically today, students should be able to construct a hazard assessment of the Earth, including recurrence intervals of different types of hazards.


How course activities and course structure help students achieve these goals:

As an example of the "Students should be able to associate geologic hazards/features with different types of plate boundaries" goal, I presented students with a variety of datasets (seismic data, focal mechanisms, volcanic data, geochronology, etc.) and they had to observe trends they saw. They then met in groups to present their findings and write hypotheses about why these patterns exist. This data-focused exercise gave students an opportunity to work with real data and exposed them to the challenges of working with complex datasets.

For the remainder of the semester, we have been working (as a class) on reconstructing the tectonic history of this portion of Maine and each student has a specific plate that they are independently researching. They were required to use primary literature to determine the tectonic history of their plate over the past 500 Myr. As part of the project, students will produce a timeline of the last 500 Myr and present it to the class. After the presentations, students will meet to determine how well their histories match up and to deduce the timing and significance of major plate motions over the last 500 Myr. They're also learning about the "messiness factor" in science--that multiple interpretations are possible in many instances.

Skills Goals

Search for and cite primary sources
Read and present research papers
Generate testable questions with multiple working hypotheses
Collect and evaluate data
Synthesize datasets
Draw figures & graphs
Develop quantitative skills


How course activities and course structure help students achieve these goals:

I used two major projects that were semester-long as my primary evaluation techniques. One was a research project about a plate that I assigned. Students were required to use primary literature to determine the tectonic history of their plate over the past 500 Myr. As part of the project, students will produce a timeline of the last 500 Myr and present it to the class. After the presentations, students will meet to determine how well their histories match up and to deduce the timing and significance of major plate motions over the last 500 Myr. They're also learning about the "messiness factor" in science--that multiple interpretations are possible in many instances.

The other major project is a geologic map and field-based project where students are unraveling the tectonic history of this portion of Maine. We visited 10 field stops, collected data (and in the process, learning about how to collect good data). Students then work together to tie together structural data, lithologic descriptions, cross-cutting relationships and primary literature to provide a concise history of this portion of Maine. Weekly lab reports have focused on collecting, evaluating and presenting data. The final project focuses on synthesizing all the data.

Assessment

1-minute papers
student reflections
quick draws
concept mapping
student presentations
weekly lab reports

Syllabus:

Syllabus_The_Plate_Tectonics_Revolution (Microsoft Word 2007 (.docx) 227kB May4 12)