EXERCISES FOR 3D ANAGLYPH MAPS: USING SIMPLE VISUAL OBSERVATION TO INTRODUCE COMPLEX GEOLOGIC HISTORIES

A series of exercises has been designed to accompany four of the 3-D anaglyph maps (available online for download) produced by the National Center for Earth-surface Dynamics. The anaglyph maps are: Eastern US, Western US, the Upper Midwest and the Mississippi River. The general philosophy behind the exercises designed for the Eastern and Western US and Upper Midwest map is to get students to use basic observation of map patterns and textures to produce a ‘geological’ map on an overlay; separating data from interpretation. As long as the students develop clear sets of criteria, their maps will be valid, and will invariably be broadly similar to published maps. Based on their observations and maps, students are then able to make predictions about relative age of geological units and events, and speculate on rock or sediment types. In the case of the Upper Midwest map, students are able to further speculate on depositional settings and environments. For the Eastern US map, students compare their boundaries to those portrayed on the USGS ‘Tapestry’ geological map, which segues into already-existing lab exercises on the rocks in question. The anaglyph map of the western US presents a very complex geological record. While an approach similar to that used for the Eastern US can be used, it can be overwhelming for students. The most effective exercises designed for this map focus on smaller regions, such as the Channeled Scablands, with the mapping exercise segueing into readings, exercises, and lectures on the geologic history of the region. The anaglyph map of the Mississippi River is used as more of a hook or centerpiece for learning about basic concepts in hydrology and geomorphology, as well as introductory aspects of river engineering. Students complete a series of lab exercises that together provide a ‘picture’ of the geologic and continuing human history associated with the river. Use of these maps provides students with a visual focus for their learning, a hook, and builds their ability to separate data from interpretation.