USING 3-D PRINTED GEOLOGIC FOLD MODELS AS TANGIBLE TEACHING TOOLS IN INTRODUCTORY GEOSCIENCE COURSES

Among the many topics taught in an introductory geoscience course, geologic structures and maps are particularly difficult for students to grasp well without good visualization tools. Interpreting the map view of plunging folds correctly or drawing a representative cross-section requires the ability to visualize these structures in 3-D, and often this is where students struggle. Our present efforts are aimed at developing and using 3-D printed geologic fold models as tangible teaching tools in the introductory classroom or laboratory setting. Multicolor 3-D models of non-plunging and plunging anticlines and synclines were designed using the online 3-D CAD app Tinkercad (www.tinkercad.com) and were printed at the Hudson Valley Advanced Manufacturing Center (HVAMC, http://www.newpaltz.edu/hvamc/) on a 3D Systems PROJET 660. While other 3-D models of folds exist, these usually are block models similar to the cardboard models found in laboratory manuals. Unlike these static block models, each of our fold models consists of two detachable parts. Removing the top half of the fold model exposes a map view of the fold on the upper surface of the bottom piece (as would be exposed after erosion of part of the fold); the vertical cross-section is visible on the front and back surfaces. An additional feature in some of our models is that the map view surface is not flat, i.e. the map view also gives a simplified topographic expression of individual units within the fold. Students not only see the exposed map view surface but also topography and how it is related to lithology and geologic structure. We implemented these 3-D fold models in our Physical Geology classroom and lab in Spring 2015. Having students disassemble and reassemble these models in class or lab helps them visualize the connections between map views and cross-section views, which are critical to mastering geologic structures. Preliminary analysis of average results on geologic map interpretation questions indicates a 4 to 8 % improvement in average scores. We would like to thank Katherine Wilson and Daniel Freedman at HVAMC for their help, encouragement and support.