FINDING FAULT: LABORATORY EXPERIMENTS AND CLASSROOM STUDIES ON IDENTIFYING FAULTS IN IMAGES

We will report on a series of classroom and laboratory studies directed at teaching students to identify faults in photographs. In the classroom studies, students in introductory geology classes were shown a set of outcrop photographs, both at the beginning and end of the semester. The students were asked whether a fault was present in each image, and if so, to identify its location. In the laboratory experiments, non-geoscience college students were shown a definition of “fault,” with or without accompanying schematic diagrams of faulted rock layers. In some conditions, the schematic diagram was a single image of faulted layers and in others the diagram was two similar images of faulted and unfaulted layers. Following the instructions, participants completed the same fault identification task that was used in the classroom studies.

In the classroom studies, students’ accuracy in identifying faults generally improved. For those photos on which students showed the greatest improvement, key factors appear to be distinguishing faults from fractures and identifying offset layering, particularly where layering is subtle and the offset is not eroded. In the laboratory experiments, initial instructions that included two similar images of faulted and unfaulted layers led to the highest performance at identifying faults in the outcrop photos. In fact, participants who were shown two similar images of faulted and unfaulted layers were approximately as successful at identifying faults in outcrop photos as geology students taking the end-of-semester post-test. We will discuss the implications of both of these studies for effective instruction to help students learn to identify faults in images.