The Sonju Project was begun at Macalester College in 1998.  Prior to this time the petrology course at Macalester College was more traditional and consisted of a lecture and weekly laboratory exercises.   The laboratory exercises included petrographic observations of different suites of rocks, and introduction to working with mineral and whole-rock chemistry, and numerical modeling.   Although this approach seemed satisfactory, student learning seemed limited by this fragmented approach; each portion of the course utilized a different suite of rocks.  Furthermore, studies of science and mathematics education were increasingly emphasizing the importance of "active learning", problem solving, cooperative learning, the use of sophisticated instrumentation, and quantitative analysis.   Many studies also underscored the need for students to experience the methods and processes of inquiry as practiced by scientists and engineers (e.g., Tobias, 1992; Felder, 1993; NSF, 1996, National Research Council, 1999a, 1999b, 1999c).

Before adopting the Sonju project, I tried several other projects of lesser magnitude; these were multi-week projects, but they were conducted in addition to more traditional laboratory exercises.   During the mid 1990's I had a series of discussions with Dr. James Miller, Jr. of the Minnesota Geological Survey about teaching petrology and suitable geological features in the region for a semester-long project.   In 1998 Dr. Miller suggested that the Sonju Lake Intrusion might be an ideal focus for a project in a petrology course and he led several local educators on an informal field trip to the intrusion that summer.   I adopted the project in the next offering of the petrology course (spring 1999) and continue to use it today.   The emphasis on the project in the course has gradually increased so that now it is used as an example for almost every aspect of the course.   Without a doubt, some important content that is covered in more traditional petrology courses has had to be abandoned in order to implement this investigative approach, but students experience an integrative approach to a real-world problem, something that is not normally in most other courses in the undergraduate curriculum.

In the current Petrology course at Macalester College, students are introduced to the Sonju project in the first week of the course when they begin learning about the classification of igneous rocks.   Soon after students begin examining the petrography of the Sonju specimens.  After a brief introduction to phase diagrams, students apply phase diagrams to understanding the evolution of the Sonju Lake Intrusion and associated Finland Granophyre.   By mid semester the students begin conducting chemical analyses of the minerals in thin section using a scanning electron microscope and energy dispersive analyzer.  This is followed by whole rock analysis of samples using x-ray fluorescence.   During the last half of the semester the students use a petrologic database software package to work with the large sets of mineral and whole-rock data to study the origin and evolution of the intrusion.   The data analysis is supplemented by numerical modeling of the major element data (whole-rock and mineral) using MELTS and the trace element data using trace element models of crystallization.   At the end of the course we hold a Conference on the Origin of the Sonju Lake Intrusion in which students give presentations and submit papers on various aspects of the Sonju Lake Intrusion.

Student and faculty comments about the project are encouraged.  Please contact Karl Wirth by e-mail (wirth @macalester.edu) or by telephone (651-696-6449) if you have any further questions or comments.