National Geographic : 2007 Mar
PHOTOJ0URNAL PAUL NICKLEN I am obsessed with the shapes, formations, and colors of ice. While diving, I found these trapped bubbles glimmering in a piece of multiyear ice (above). Pressure cracks slash across lake ice on Ellesmere Island (below). Ice can get up to 12 feet thick in this area; this slab was at least eight feet thick-and probably more.