An Electron Microprobe in the Classroom: A Remote-Access System for Education

Ellery Frahm

Electron Microprobe Laboratory, University of Minnesota-Twin Cities

The system has been used for a variety of course types and levels, principally undergraduate petrology and mineralogy courses.

Students should know at least some introductory mineralogy; in addition, readings or basic descriptions of the electron microprobe provided beforehand are helpful.

Professors have used our system at various points in undergraduate petrology and mineralogy courses.

Various topics can be addressed: mineral identification classification, mineral formulae, pressure-temperatue determinations, common mineral assemblages, and so forth.

Decision making; clarification and application of mineralogy and petrology knowlege; students engaged analytical process; students can, for instance, view electron images of a thin section, ask for certain grains to be analyzed, and see the resulting X-ray spectra; data are collected from the students' own samples, and students are involved in the decisions made during electron probe microanalysis.

Exposure to state-of-the-art instruments used to analyze geologic materials; seeing the "real thing" vs. reading a book description; learning about modern instrument operation, data acquisition, and analysis procedures.

Our remote access system permits students to interact with our electron microprobe and obtain visual information about the tasks performed by lab personnel. Students in a petrology class, for instance, can view backscatter-electron images of a particular sample, ask for specific points to be analyzed, and immediately see the resulting spectrum of characteristic X-rays. With this interaction, such an exercise is more much pedagogically effective. Our video streams mean that students do not need to know how to operate the instrumentation -- that is not the point for students in a mineralogy or petrology course. Instead, seeing a live backscatter-electron image or an X-ray spectrum from a point they chose catches the interest of students and allows them to make decisions while they learn about mineral associations. Many classrooms are now equipped with Internet connections and a computer with a projection system. As a result, a lecturer in such a classroom can project our video streams onto a screen or wall so that the entire class can observe the analysis of a sample. Lab rooms also often have internet-capable computers, so a small group of students could, on the phone, ask lab personnel to move to some point on a sample and examine a specific crystal.

Evaluation can be the same as a similar textbook-based lab exercise; professors or TAs can also facilitate and ask relevant questions during the session.

http://probelab.geo.umn.edu/remote.html