This is inside the ice cave. The blue color, I was told, results from the light filtering through approximately 90 feet of ice, leaving only the blue wavelengths. Higher up the wall, where the light is passing through less ice, more wavelengths are visible and hence the light appears "whiter."
For me, the beauty is in the ice per se, the sculpturing, warping, wrapping, flowing "fabric", feathers, facets, cracks, bubbles. In places it reminded me of Michael Angelo's David. And, there in the middle of this smooth delicacy, a boulder, harsh, stark.
Incidentally, the "sand" floor is actually ground dirt, sand, over top of more ice.