Why do dried clay and salt crusts curl and flake on playas?

The curling and flaking of clay and salt crusts on playas is primarily a result of the physical processes of drying and sediment contraction.12

As the moisture evaporates from the surface, the clay and salt deposits undergo significant shrinkage. The extent of this volume change is influenced by the specific clay minerals present, with smectite clays experiencing the most pronounced shrinkage. The presence of salts further intensifies this effect, as the deposition and crystallization of salts within the developing cracks create a network of wedges that contribute to the structural breakdown of the surface.1

Once these crusts dry, they become susceptible to wind deflation, which lifts and transports the curled and flaked sediments to surrounding areas. This process is a significant environmental factor, as it can create dust hazards in regions where these surfaces are exposed.2