Evaporite

Evaporite (German evaporate from Latin evaporare =) defines evaporation and Eindunstungsgestein, which mainly occurs as a chemical sediment in the continental crust and which is characterized by progressive evaporation ( evaporation) forms from sea water in order of increasing solubility. It interferes with the progress of evaporation of water in the arid climate in a sea or lake basin from.

Among the constituents of evaporites include:

• First ( and thus in the sequence at the bottom ), carbonates ( limestones and dolomites )
• Then: sulphates (gypsum, anhydrite )
• Then: halides ( halite, sylvite )
• Last: potash and magnesium salts (Epsom salts, tailings or inert salts, carnallite, sylvite, kainite )

These are made ( from sparingly soluble to slightly soluble) with progressive evaporation of water at the pelvic floor in the specified order. This sequence can be multiple, partly incomplete, repeat.

Although the water evaporating various salts are dissolved halite rocks occur pretty pure because the various salts different solubilities (expressed as a solubility products ) have. Therefore, the salts reach saturation solution at different concentrations and therefore are covered when reaching different from high concentration. For this reason, anhydrite occurs, for example in southern Germany on rock salt before.

Thickness of layers of the same salt can arise when performing regularly new water with dissolved salts, eg via a land bridge and a lake fills again. Here, the already deposited layers are partially or completely dissolved again until again a saturated solution is obtained (or the deposited layers are consumed) and the further evaporation, in turn, first issue the salts present in the solution at the gesättigsten.

These processes are also used in solar salt works as a method for the extraction of sea salt by seawater is pumped into shallow pools and there evaporated by the sun. The pools are regularly replenished with additional sea water until the sea salt precipitates. This is then removed and dried.