The SEM can magnify from six to one million times. It can zoom in on something as small as 3 microns, or three-millionths of a meter.

A small, clear box with several basalt fragments represents a key part of Courtney Porter's thesis project.

Each fragment, though no bigger than a coffee bean, was trapped deep underground until recently, and each piece tells a unique tale of how water and rock interacted to produce minerals.

To the naked eye, the pieces give a hint of a story, in green and reddish shades of deposit clinging to the usually black rock. But under the precise beam of a scanning electron microscope, those slight deposits and crevices become valleys and craters, as the surface is magnified thousands of times.

Porter, a geochemistry senior at Whitman College, secured the basalt pieces from a dig at Wallula Gap through her internship this summer with the Pacific Northwest National Laboratory. The group is exploring trapping carbon dioxide underground, to rest between layers of ancient rock.

"It's a way of keeping it from acting as a greenhouse gas," she said.