The University Record, December 18, 2000

Virtual reality CAVE simulates trip to Earth’s core

By Nancy Ross-Flanigan
News and Information Services

In Journey to the Centre of the Earth, Jules Verne took readers on an amazing expedition into the heart of the planet. U-M geologist Peter Van Keken takes students and fellow scientists on equally marvelous tours—skittering around subduction zones and zooming in on earthquake activity. But instead of using picks, axes and ropes as Verne’s characters did, Van Keken employs virtual reality to explore Earth’s inner reaches. In an invited presentation to the American Geophysical Union Dec. 16, Van Keken described how the use of virtual reality in the geological sciences can foster collaboration, enhance education and advance research into such complex processes as mixing behavior in Earth’s mantle.

Van Keken and colleagues at the U-M, University of Minnesota and University of Colorado at Boulder use virtual reality tools to “get inside and walk around” three-dimensional representations of data, discovering new patterns and relationships. The researchers can literally immerse themselves in their data using facilities such as the Media Union’s CAVE, a 10 x 10 x 10-foot room in which full-color, computer generated stereoscopic images are projected onto the walls and floor. Users wear special goggles that make the data appear as three-dimensional features around the viewer. They also can use a joystick and a wand to move images around and point out interesting features.

“Using this technology, I’ve been able to see and understand processes I probably would have missed by just looking at two-dimensional plots of the data,” says Van Keken, assistant professor of geological sciences.

Van Keken’s research focuses on plate tectonics and the dynamics of the mantle, the plastic-like layer between Earth’s crust and core. A specific area of interest is understanding mixing in the mantle, which is essential in piecing together a picture of Earth’s chemical evolution.

Van Keken says the virtual reality visualization approach has benefits not only for individual researchers, but also for interdisciplinary teams whose members may have different backgrounds and vocabularies. As virtual reality becomes more widely used and more researchers have access to CAVEs or 3-D graphics workstations, team members in different locations will be able to see and manipulate the same images at the same time.

Already, the software that Van Keken uses allows a long-distance collaborator to “visit” the CAVE by inserting a representation of himself or herself in the image being viewed. The virtual visitor can then walk around and point out features in the image just as the real researchers in the CAVE can.

Because room-sized CAVEs are still expensive and rare, Van Keken and colleagues design their visualizations so that at least some features can be viewed on regular desktop computers. For example, they use advanced visualization and virtual reality techniques to help students see how the spatial distribution of earthquakes relates to forces along the edges of the sections, or plates, that slowly move around on the mantle.

“The first time I visited the CAVE and used this immersive technology, I felt I became part of my own models and data rather than being a remote, outside observer,” Van Keken says. “It can provide a fundamental shift in the way we approach understanding the dynamical structure of the deep Earth, which is inaccessible to direct investigation.”