GOVERNMENT

BLACKSBURG, VA -- When looking at the physical and chemical evolution of continents through time, geologists are faced with thousands and thousands of pieces of information that might fit together to describe the process better. John R. Wilson, a former graduate student at Virginia Tech, and his advisor, A.K. Sinha, professor of geological sciences at Virginia Tech, are experts on the subject of plutons, or bodies of rock such as the rock that hardens far beneath a volcano. Even with that specialization, looking at the place of plutons in the evolution of continents involves so much data that it can be difficult to find and plot it all in any timely manner. So the two have developed, using a Geographic Information System (GIS), the template for a database of attributes of plutons that allows geologists to interpret in new ways the tectonic history of a region. Wilson, who is now laboratory coordinator for the Department of Geology and Environmental Geosciences at Lafayette College in Easton, Pa., said that, with the new system, geologists can more easily interpret large amounts of data. "In the past," Wilson said, "scientists had to go from memory or look through publications and theses and make a list. The information was not easily accessible or queried." The new database system within a GIS allows scientists to look at and interpret data over a large area in new ways and in a variety of ways at once, he said. That allows them to ask new questions of the data. "We can query the data to show us all the plutons of one type and all the plutons within a certain age range, and we can see new spatial relationships of plutons and the regions they are in." "We have a cascade of scales," Wilson said. The GIS allows the scientists to look for spatial relationships within the data. For example, they can zoom into an outcrop (any rock formation in the woods or fields or on road sides) and determine its attributes—the minerals present, the properties of the rock, and so forth. "At the same time, we can zoom in on the minerals and their properties or zoom out to a more regional scale and compare that outcrop with one far away." "Everything has a location," he said. That provides information on spatial relationships. Using the GIS, the attribute data (what is at the outcrop) from the new database can be applied to the spatial data so scientists can look at more data with greater ease. They can better manage the data and use it to plot relationships between locations. For example, if they have data on plutons in Virginia and someone else has data on plutons in Massachusetts, they can then compare the chemistry, ages, and other characteristics of the rocks. "This helps scientists understand the regions of the Earth, why they are as they are now, and how they got that way," Wilson said "This advances our science." Wilson and Sinha have created the template or framework that will allow them to include attributes of plutons in a database format. They also designed the database template to be used in conjunction with databases developed by geologists whose expertise is in another area, such as sedimentary rocks.