TEACHING INSTRUMENTATION IN AN ADVANCED UNDERGRADUATE GEOCHEMISTRY COURSE

Geological instrumentation (XRD, XRF, ICP, IC) at Albion College is taught primarily in the environmental geochemistry course, which is based on the philosophy of teaching instrumentation in context of the application of data generated. Students in an Environmental Science Concentration, with majors in geology, biology, and chemistry are the target audience; mineralogy or inorganic chemistry is prerequisite. The goals of the course are for the students to gain: 1. a working knowledge of instrumental techniques, 2. a basic understanding of composition of common rocks and surface waters and 3. an understanding of the processes and chemical principles that govern this distribution and the fate of anthropogenic contaminants.

For each technique, lectures on instrumentation principles are followed by methods labs on practical aspects, method development and sample preparation. Lectures on geochemical principles are then supported by project labs, in which materials are analyzed and results interpreted. These labs include 1. Bulk chemical and mineralogical analysis of a suite of igneous rocks (XRF, XRD) followed by spreadsheet modeling of major and trace element evolution. 2. Analysis of local surface and groundwater (ICP, IC) followed by charge balance calculation, speciation and saturation index calculations using Visual MINTEQ. 3. A cumulative project such as analysis of foundry sand and associated water, with results compared to MINTEQ modeling of expected mineral/water interaction, and experiments with adsorption of heavy metals by local soils as a possible means of explaining differences.

The class has proven to be an effective way to introduce biology and chemistry students to mineralogy as well as geochemistry through continued work with common minerals. It has also helped geology students with chemistry by teaching principles in a geologically relevant context.