Volume 3, Issue 22 August/September 2006
Mapping the Future of Field Geology
George Brimhall also teaches a groundbreaking undergraduate course titled, "Crossroads of Earth Resources and Society: Iconic Events in American History and Their Influence Today."
In 1818, William "Strata" Smith ushered in the modern practice of field geology with his publication of the first hand-painted, color geological map of England and Wales. Two centuries later, the tools haven't changed much. Recently though, UC Berkeley geologist George Brimhall and his colleagues have developed mapping software that they hope will bring field geology kicking and screaming into the digital age.
Today's field scientists use paper topographic maps and a box of colored pencils," says Brimhall, professor of geology in the Department of Earth and Planetary Science. "They're using technology from the second grade to map complex problems in geology of great importance to society."
Brimhall's software application GeoMapper leverages two developments in information technology. Geographical Information Systems (GIS) are tools for the creation, access, and analysis of high-resolution spatial data. The GIS digital maps enable the easy correlation of data from different sources. For example, aerial photography of a region might be overlaid with rainfall information and land use maps or geophysical maps of earthquake epicenters and magnitudes. Google Earth is one example of a GIS. However, the systems available to geologists provide much higher resolution of features on the ground. Indeed, GIS has been a common laboratory research tool for geologists for some time, but in the field, paper still reigns supreme.
Using GeoMapper, Brimhall and his colleagues created a map of mine waste dumps in Spenceville, California. The team flew in a helicopter over the site to take infrared spectra samples of the ground below that provided insight into the surface mineralogy. (courtesy the researchers)
Currently, a geologist might walk across a piece of land with a paper map in hand. As she recognizes various kinds of rocks, she colors those on the map. For example, a red band might indicate shale while blue pencil denotes granite. Back in the lab, that data from the field must then be entered manually into the computer so the new information can be overlaid on top of GIS maps. Brimhall's approach is to eliminate that middle step through inexpensive portable computers, GPS technology that pinpoints your exact location on the planet, and innovative software. The software provides a scientifically intuitive user interface of pictorial "buttons" to map and label rock types, faults, structures, and earth resources. Using a portable PC equipped with a stylus interface, the geologist an click directly on the pictorial buttons and "write" directly on the screen. A small GPS system plugged into the tablet keeps track of the user's location in the field.
A map with a legend showing a portion of the interpreted surface mineralogy at Spenceville. (courtesy the researchers)
"The result is that the field geologist can do that visual translation, writing observations about the rocks and structures, directly into the GIS system right then while their location is automatically recorded," Brimhall says.
GeoMapper is used to create these maps in the field. Of course, data capture is just one of the benefits of the portable mapping system. The technology isn't just for making digital maps, but accessing them as well.
"You can load satellite images, detailed topographic maps, and field data onto the tablet PC so you can view a huge amount of 3D geospatial information while you're outside," Brimhall says. "This brings information to the geologists when they need it, out in the natural environment, not just when you're sitting at your computer back in the office."
In one experiment, the researchers tested the system's value in screening abandoned mines to identify those most in need of environmental remediation. The team employed a chemical spectrometer to identify areas with the most
In one early demonstration, the researchers used GeoMapper to create a raised-relief scale model of the University of California, Berkeley campus 3 by 6 feet in size for use by blind and disabled students to learn their way around the campus. (courtesy the researchers)
"Instead of having to walk every square inch of ground, you can spend your time much more judiciously just by virtue of having this information on your computer with you," Brimhall says. "This is really about making science portable."