Huge amounts of sand were needed to build Kelso's delicate wind-created sculptures, but geologists studying the Preserve discovered that no new sand is moving in to replenish the dunes. The Kelso Dune sands remained a mystery until very recently. Wind blowing from the northwest gradually carried the sand southeastward. In the path of the prevailing winds lie the Providence Mountains and the pink pinnacles of the Granite Mountains . The rocky crags and sloping fans of the two ranges block the moving sand.
Sand piles up at the base of the mountains and along their flanks, forming dunes and sand sheets.
Where the sand piles up researchers found that the dunes are actually made up of several sets of dunes, stacked one on top of another. This happens whenever the climate is dry enough to expose the raw material of dunes, sand, to the wind. In fact, most of the eastern part of the Kelso Dunes formed when water-filled Soda Lake and Silver Lake dried up, exposing the lake bottom sediment. The entire dune system was stacked up in five major pulses over the past 25,000 years. As you explore the dunes look for tracks left behind by the many creatures that call these dunes home.