White Sands

This is a shot from the White Sands National Monument in New Mexico. Whitesands is an area of bright white sand dunes composed of gypsum crystals. Gypsum is rarely found in the form of sand because it is water-soluble. Normally, rain would dissolve the gypsum and carry it to the sea. Since the Tularosa Basin has no outlet to the sea, rain that dissolves gypsum from the surrounding mountains is trapped within the basin, and the rain either sinks into the ground or forms shallow pools which subsequently dry out and leave gypsum in a crystalline form on the surface. The dunes constantly change shape and slowly move downwind, covering the plants in their path. Some species of plants, like the Yuccas in this picture, however, can grow rapidly enough to avoid being buried by the dunes.