Teaching notes


Audience: undergraduate-level petrology or volcanology course

Skills and concepts that students must have mastered:
  1. the terms "mafic", "intermediate", and "silicic"
  2. some knowledge of incompatible element behavior may be useful, but is not required

How the activity is situated in the course: This activity could be used early in an igneous petrology course to introduce the concept of petrologic diversity. This exercise does not require the students to interpret the geochemical data or to formulate detailed petrogenetic hypotheses; instead the main purpose of this exercise is to encourage the students to analyze, compare/contrast, and ask questions about volcanic rocks using geochemical data.


Content/concepts goals for this activity: Students who complete this exercise should be able to:
  1. use the NAVDAT database to obtain geochemical and age data from ten volcanic fields in North America
  2. note differences and similarities between geochemical and age data from various volcanic fields
  3. answer simple questions concerning the datasets
  4. ask new questions based on what they observe from the datasets

Higher order thinking skills for this activity: This exercise requires students to compare/contrast data and to ask novel questions based on their use of data.

Other skills/goals for this activity: Obtaining and using data from online databases like NAVDAT informs the students about the powerful resources that have recently become available to the scientific community via the creation of digital cyberinformatics and cyberinfrastructure. Carefully guiding students into these databases, through the various steps required to screen, download, import, and use their data, empowers the students to think and act like scientists in tangible, practical ways.


The exercise is written so that the students fill out a table with the data they obtain. It is up to the instructor how the students' data might be evaluated. The "wrap-up" questions at the end of the exercise could provide a basis for a class discussion.