Death Valley, Calif.—The dozen students and scientists spread over an area called Furnace Creek look like cyborgs in floppy hats scrabbling over the boulders. They inspect rocks with magnifying lenses held up to eyeglasses sporting miniature cameras and infrared lights, then hammer chips off them.
A seasoned geologist could tease out a history of earthshaking clashes from evidence in the terrain here. A break in a steep gray slope, for instance, suggests a fault at work fracturing the landscape. The aim now of these cameras is to see how researchers’ eyes dart across this scene, to understand how experienced minds unconsciously scan the world for clues that point the way to discoveries. The hope is that one day scientists will be able to train neophytes with virtual-reality displays that simulate environments of interest.
“We know a lot about how to educate people on facts, but we know almost nothing about how to educate people on acquiring perceptual skills other than lots of repetition, which can be very time-consuming and expensive,” says cognitive scientist Robert A. Jacobs of the University of Rochester. “It would be great to develop more effective training procedures.” Such research could go well beyond geology, too, and delve into how detectives analyze crime scenes or soldiers look for camouflaged targets.
For teaching geologic expertise in Death Valley—where the driest, hottest and lowest places on the continent are found— the key is a wearable eye-tracking device that can monitor what people look at in a natural environment. It consists of two lightweight video cameras mounted on eyeglass frames—one pointed at what a person is seeing, the other pointed at the person’s right eye—tracking its movements with the help of a little infrared LED that shines an invisible beam onto the eye. Two camcorders in a slim backpack record data that eye-tracking programs then process later.
The novice and seasoned geologists from the University of Rochester have gone out with the eye trackers about four times a day over their two-week field trip across California, which took them from San Francisco by the San Andreas Fault through the snowy Sierra Nevada near Yosemite National Park to the harshest area of the U.S. “Death Valley is a great place, where one can really see active geology firsthand—forces that are shaping the crust of the earth,” says geophysicist John A. Tarduno, another of the Rochester scientists. “Most people think of Death Valley as this big hole because it’s below sea level, and that’s true at the heart of it, but right adjacent is an 11,000-foot mountain.”
Nature does not like such elevation differences right next to one another; erosion tends to even things out. “The fact we have a valley today hints at active processes to maintain that difference,” Tarduno explains. “It is conclusions like these that we hope to see students reach by themselves.”
As with almost all field trips, unexpected troubles arose, such as the sandstorm that engulfed Death Valley on the first day, which sent the group to a campground at the snowline of Mount Whitney, the highest point in the contiguous 48 states. The desert is trouble in other ways—the glint of the sun off the eye can confuse the eye-tracking software, which is why the experimenters donned ungainly wide-brimmed sun hats. Even so, the software loses track of gaze in about 10 to 15 percent of the video frames the cameras record, a problem future algorithms might fix.
Aside from the eye trackers, the researchers also used a robot-operated camera to take hundreds of high-resolution photographs of the areas, which will later get stitched together for panoramic images displayed on giant wraparound screens. “The hope is we verify that student geologists in the field and those surrounded by these virtual environments view formations the same way so we can use simulations to train novices on dozens of virtual field trips, cutting down on the costs of travel and equipment to make better use of actual trips,” says imaging scientist Mitchell R. Rosen of the Rochester Institute of Technology.[break]
Those flashes of discovery are what the researchers are seeking to record now. At the Long Valley caldera, Tarduno quizzes students about the lava flows they have seen and the curve of surrounding landmasses until they realize they are standing in a dormant supervolcano roughly 20 miles long, 11 miles wide and covered in snow. “I was really excited at that instant,” student Shannon Moss recalls. “I saw this circle we were in, and it just came to me.” An otherwise fleeting moment now captured by the eye trackers.