Field instruction is a critical piece of undergraduate geoscience majors' education, and fieldwork remains a major part of the work of professional geologists. Despite the central importance of field education, there exists relatively little educational research exploring how students learn to solve problems in geological fieldwork. This study adds tools and insight to the study of field problem solving. We used GPS tracking of students engaged in independent field examinations, and developed two parallel coding approaches for analyzing student navigational choices. Taken together, our coding enables correlation of navigational characteristics with performance and lends insight into problem solving by building on a conceptual framework modified from the cognitive science field of Naturalistic Decision Making. Our results indicate that most advanced geology undergraduates are capable of recognizing important features in the field, however lower-performing students fail to systematically test multiple interpretations of their data as reflected in poorly planned traverses across the examination field area. Specific track sequences, especially those involving reoccupation of locations, show particular difficulties in aspects of problem solving that are reflected in low quality interpretations on finished maps. Our study offers new tools and an independent approach to gauging student skills in geologic field problem solving.