INCORPORATING GEOCHEMISTRY IN AN EARTH SCIENCE CURRICULUM

Many students have the tendency to shy away from anything related to chemistry. In doing so, basic principles learned in their freshman chemistry course are often forgotten. This is detrimental to future learning as basic principles will be assumed known in upper level courses. A review of a recent geochemistry course class list showed that the average grade in the freshman chemistry course was a B. These same students, however, struggled with many simple concepts and calculations such as pH and mass balances. In an effort to improve chemistry skills, I designed lab exercises in two other courses, physical geology and hydrogeology to 1) reinforce basic chemical principles and calculations, 2) demonstrate the value of chemistry in solving problems in other geoscience disciplines and 3) provide students an opportunity to use chemistry in a more “interesting” way. The geochemistry course also has been redesigned to include an independent project in lieu of traditional labs. Assessment of the success of this project involves several qualitative and quantitative tools including course evaluations, student comment forms, pre- and post-testing, targeted questions, and concept mapping. Preliminary results indicate that the new exercises have a positive impact on overall student learning, but sample sizes in many cases are still to small to be conclusive. Qualitative results are strongly positive. In the physical geology, students are engaged in a two-week field-lab exercise that uses stream chemistry to evaluate bedrock geology and anthropogenic impacts. Along with data on discharge, sediments and topography, students evaluate the local geology and environment near campus. Student comment forms were all positive with regards to this assignment, and many suggested that the entire lab be structured in this way. In the groundwater course, students are engaged in a 9-week lab project with geochemical samples from both field and lab experiments. The goal is to integrate concepts across numerous geoscience disciplines. Students generally liked the project-based lab. Finally, in the geochemistry course, 5 of 11 students continued their course project in independent projects that are leading to conference presentations or journal articles. Several of these students were not among the top performers in the class.