USING GOOGLE EARTH AND VIRTUAL 4-D ANIMATIONS FOR TECTONIC RECONSTRUCTIONS

Cognition of challenging geoscience concepts such as geologic time, plate tectonics, and Earth’s layered structure is greatly facilitated by animation, but many simplified visualizations unknowingly introduce or reinforce misconceptions. The advent of 3-D virtual globes, such as Google Earth and ArcGIS Explorer, has dramatically improved our ability to create compelling, effective, and accurate visual presentations of complex geology and tectonics. Virtual globes are intuitive to use and generally free to the public. The standard KML file format is easy to code for programmers comfortable with XML scripting, and built-in tools in ArcGIS, Google Earth, and other platforms allow for easy portability of spatial data among formats.

The potential of Google Earth-based maps, models, and animations for geoscience education and research is well documented. However, there has been little development in the use of Google Earth for presenting tectonic reconstructions. Tectonic concepts are less intuitive for geoscience novices and the general public to comprehend, as they require the ability to 1. visualize geologic maps and structures in 3-D, and 2. understand how these structures and geology change through time. Virtual globes provide an interface for exploring geology and tectonics at all scales, and the time stamp feature provides an easy mechanism for animating geologic and tectonic processes through time.

As a proof of concept for the utility of virtual globes for tectonic reconstructions, we have updated (and simplified) the Whitmeyer and Karlstrom (2007) series of tectonic maps of North America and animated them in Google Earth. The map sequence is targeted at general audiences and multiple learning levels of geoscience student audiences, such that the maps can be viewed individually or animated through time. Though this new format provides a definite improvement over the original Powerpoint animation, we realize that we are only scratching the surface of the visual potential of the virtual globe format. Future work will augment the tectonic reconstructions of North America to include Phanerozoic orogenic cycles of the east and west coasts, and include sequential, vertical cross sections to show lithospheric structure at depth through time, as is now coming into sharper focus from EarthScope data and images.