Water Deposits

In mountainous regions, the intermittent streams are confined, but as they empty into a valley, the streams spread out, lose energy and deposit sediment.

The resulting series of braided streams eventually builds up an alluvial fan at the canyon mouth.

Overtime, alluvial fans from adjacent canyons coalesce to form the bajada.

If a pediment is present, the bajada lies basin-ward and together they form the Piedmont.

After an intense rainstorm, water pours out of the canyons and across the piedmont. If a pediment exists, water rushes across it to the bajada, where a substantial proportion of it soaks in. However, a portion of the water may end up ponding to form temporary lakes or Playas. Evaporation of playa lakes results in the formation of evaporite minerals (gypsum, halite).