USING GIS TO TEACH GEOSCIENCE: BENEFITS AND LIMITATIONS

With advances like Google Earth-Moon-Mars, students can “fly” through three-dimensional representations of the valleys of Vallis Marineris or around the flanks of Olympus Mons on Mars, explore the impact craters and basins of the Moon, or even the depths of our oceans. Using a GIS and high-resolution imagery and digital elevation models; geomorphological features and structural relationships can not only be identified, but in some cases, measured. Students can explore the fundamental cross-cutting and embayment relationships that determine relative age dating of surfaces, and if multi- or hyper-spectral data is added, even the composition of surface features. A GIS can be used to create geologic maps, explore sea level change and its impact on coastal areas, or as a way to take virtual field trips to places that would normally be difficult or impossible to experience in person, to name just a few of its capabilities.

Indeed the prevalence of remotely sensed data that is available for the Earth, and several other planets and moons in our solar system, might make it seem like it is no longer necessary to take students into the field to learn about geology at all. But using remotely sensed imagery and data also has its limitations. It is often incapable of resolving extremely fine detail, can be seriously influenced by data processing, and may lead to inaccurate interpretations if students do not have an adequate understanding of the data they are using. Sufficient field experience is still required to understand the relationships that exist, or do not exist, between different rock types, how they weather in different climates, and how to determine when something you see in an image does not make geologic sense within a greater context. GIS is a very valuable tool in teaching and analyzing remotely sensed geologic data, but should be used to supplement a sound field-based approach to teaching geology in the 21^st century and not replace it.