Gypsum sand is formed from sand-sized crystals of gypsum that originate in specific desert environments and are then transported by wind.
The Formation Process
Unlike typical sand grains derived from weathered rock like quartz, gypsum sand originates chemically within the ground. The process involves mineral formation and wind action:
- Crystal Formation: Sand-size gypsum crystals, composed of calcium sulfate with water, form within the top layer of moist, salty clay found on the desert floor. This happens when mineral-rich waters evaporate, leaving the gypsum crystals behind.
- Drying and Release: As the moist, salty clay dries out, the gypsum crystals are no longer bound within the saturated sediment and become exposed on the surface.
- Wind Transport: These lightweight gypsum crystals are then picked up and moved by the wind.
- Accumulation: The wind deposits the transported gypsum crystals, leading to their accumulation and the formation of gypsum dunes.
Essentially, the process begins with the in-situ (in place) growth of gypsum crystals in the desert soil, followed by their release and transport by wind to create sandy deposits and dunes.
