INNOVATIVE GOOGLE EARTH VISUALIZATIONS OF THE APPALACHIAN - CALEDONIAN OROGENY IN EASTERN NORTH AMERICA AND WESTERN IRELAND

Our experience teaching regional geology on field trips in New England and Virginia, and at field camp in western Ireland reveals that all but the best students have great problems visualizing geologic features in three, not to mention four, dimensions. We have developed visualization solutions for the Appalachian geology of the eastern United States and the Caledonian geology of western Ireland using Google Earth (GE) overlays and solid modeling software. GE ground overlays permit students to see their own field slips draped on the GE DEM and to learn the rules of mapping in an interactive learning setting. Student work can be compared with published maps by layering with varying transparency. Cross sections, block diagrams, surface bump-outs, fence diagrams, etc., can be added using solid modeling software. Students react with enthusiasm when they are in control of interactive 3D visualizations of their field work, such as "flying over" geology that they have repeatedly visited on foot. In the past, we have employed high-end GIS and lower-end Flash (swf) applications with significant success. However, the interface simplicity, familiarity, universal availability, and innate appeal of GE makes it a medium of choice for future course development.

In this study, we drape both published professional and unpublished student maps over the present-day virtual topography of GE and overlay field slips and notebook data for comparison and verification. We also use combinations of maps and cross sections to create block diagrams and irregular-shaped surface bump-outs within the GE environment. Future plans focus on involving students in solid modeling as well as surface draping and will address the problem of reconstructing the synorogenic (Paleo) DEM using an nth-order icosahedral model of the Earth. We expect that Google Earth and similar virtual globe technologies will play an increasingly central role in the presentation and analysis of geologic data in the future, not only for pedagogy, but also for professional mapping and research.