Field instruction is a critical piece of undergraduate geoscience majors’ education, and despite its central importance, relatively little educational research has explored how students learn to solve problems during geological fieldwork. This study adds to work presented in previous studies by our group using global positioning system (GPS) tracking of students engaged in independent field examinations. We examined four students from our previous studies working in a new field area. We also applied a new variant of our polygon coding approaches for analyzing student navigation tracks to gauge the sensitivity of our method to the time scale of analysis. We captured position data at 1 min intervals and then coded the resulting data by generating 5 min and 15 min sequential polygons. Our analysis shows that the two methods are comparable at the coarsest scale, but that finer-scale coding reveals more detailed movements related primarily to identification of key features and lithologies, which lends insight into effective geologic problem solving in the field. Coherence of small-scale and large-scale coding is most useful for showing longer-range planning in problem solving as the large-scale movements average out small-scale investigatory moves. Our results also suggest that in detailed and difficult field areas with topography that permits easy reoccupation of critical areas, there is an optimum amount of relocation and back-tracking. Too much retracing indicates confusion, as found in our earlier study. However, too little reoccupation of key areas appears to accompany a failure to recognize important features. Our study offers additional refinement of instructional tools in gauging student skills in geologic field problem solving offered by GPS tracking.