What Are Salt Flats and How Are They Formed?

Salt flats are areas of land where the salt from water with high salinity evaporates at such a high level that it is left behind in its crystalized form. This usually occurs because the rate of evaporation exceeds the amount of precipitation required to restore the water to the land. These lands are usually salt lakes or areas near coastal regions where seawater can access. This is because fresh water does not have a sufficiently high salt content.

The salt pans need to be in enclosed regions, otherwise water from other sources such as the sea or rivers will refill them. It is the action of the sun which facilitates the evaporation since the heat evaporates the large surface area of the water. There are other factors which result in the formation of a salt flat which we detail further below.

Salt flats are formed naturally through geological and climatic processes that allow the accumulation of salt concentrations from water water. Here's an overview of how a salt pan forms:

1. Salt water source: the first necessary condition is to have a salt water source. This can be sea water or water from saline lakes. Seawater is the most common source for the formation of salt flats.
   
   
2. Coastal location or in endorheic basins: salt flats are usually found in coastal regions or in endorheic basins. The latter are areas where water has no outlet to oceans or seas and tends to accumulate in saline lakes.
   
   
3. Evaporation: the key process in the formation of a salt pan is evaporation. The land area which results in a salt pan must have high evaporation rates, necessitating the climate to be warm and sunny. Evaporation causes the water to evaporate and leave the salt behind.
   
   
4. Salt concentration: as water evaporates, the concentration of salts in the remaining water increases. In some cases, seawater is directed to shallow ponds or basins designed to facilitate controlled evaporation.
   
   
5. Salt crystallization: when the concentration of salts reaches a critical point, the salt begins to crystallize and settles on the bottom or surfaces of the salt pans.

Learn more about the types of areas which can lead to salt flat formation with our article on whether there are salt lakes.

Many people will understandably be confused by the difference between a salt flat and a salt evaporation pond. This is because they both result in crystallization of salt from saline water due to evaporation. They look very similar and required large water basins on land with a widespread surface area. The key difference is that salt flats are natural and evaporation ponds are manufactured.

Evaporation ponds are artificial salt flats which are created for use by industry. The salt we keep on our table or use in our kitchen needs to be harvested. One of the most common ways, especially for salt marketed as ‘sea salt’ is to use artificial salt flats. Some of these salt evaporation ponds use existing natural salt flats and amend them for industrial purposes.

A fun fact is that different evaporation ponds can be of different vivid colors. This is due to the presence of algae which change color depending on the salinity of the water. These can be bright pink, orange, red or green.

The salinity of water is an important factor in how bodies of water are classified. We expound upon this with our article asking what is brackish water?

There are several types of salt flats, classified according to various criteria. These include their origin and geographical location. Here are some common types of salt pans:

• Sea salt flats: these are natural salt flats found in coastal areas where sea water is introduced into shallow ponds and allowed to evaporate naturally to obtain the salt. Artificial salt evaporation ponds are also often found around coastal areas since they are close to the natural resource of salt water and they don't have to transport them.
  
  
• Inland salt flats (endorrheic): in regions where water has no outlet to an ocean or sea, such as endorheic basins, saline lakes and salt pans can form.
  
  
• Mountain salt flats: in some high mountain locations, such as the Andes or the Himalayas, salt flats can be found where water from salty springs or underground sources is concentrated and collected. These ecosystems function differently from those at a lower-altitude, something you can learn more about in our article on Andean plants and animals.
  
  
• Alkali salt flats: also known as alkaline lakes, these salt flats form in endorheic basins and have a high content of alkali salts.
  
  
• Beach salt flats: on some beaches, especially in arid climates, saline water can collect in natural pools and evaporate, leaving salt behind.
  
  
• River salt flats: in certain rivers with high concentrations of salts, the waters can be diverted into ponds or canals where evaporation takes place to obtain the salt. These are rare since not many saline rivers occur naturally.

There are also different types of artificial salt flats which are used by humans to develop salt deposits. These include traditional salt flats which were used by ancient civilizations. These have been important for a long time since humans have been consuming salt in this way for over 5,000 years^[1]. Modern industrial salt flats use advanced technology and machinery, but they still function in the same basic way.

One modern improvement is the use of greenhouses to accelerate the evaporation process. This is particularly useful in areas with less sun and heat.

Learn more about how humans use and protect natural resources with our article on types of aquifers.

Salt pans play a crucial role in various ecosystems, as well as having great importance in society and the economy. Some examples of the importance of salt flats include:

• Production of salt for human consumption: salt is a fundamental seasoning in cooking and is essential for the human diet. Salt pans provide a sustainable and economically viable source of salt for human consumption.
  
  
• Food industry: salt is widely used in the food industry for food preservation, preparation of food products and improving the taste of various foods and products.
  
  
• Chemical industry: it is also a key component in the production of various chemicals, including chlorine, caustic soda and other chemical compounds essential for various industrial applications.
  
  
• Road deicing: used as an agent to melt ice on roads and sidewalks in regions with cold climates. This use contributes to improving road safety during winter conditions.
  
  
• Textile industry: salt is used in textile dyeing and finishing processes.
  
  
• Water treatment: some salts, such as sodium chloride, are used in water treatment for disinfection purposes.
  
  
• Pharmaceutical industry: it is used in the manufacture of medicines and has applications in the formulation of pharmaceutical products.
  
  
• Leather industry: in leather processing, salt is used to preserve the hides and prevent their decomposition during the tanning process.
  
  
• Power generation: in some power plants, salt is used in water treatment processes and as a heat transfer fluid in thermal energy storage systems.
  
  
• Tourism and health: some salt flats, especially those with unique geographic and landscape characteristics, may also have tourism and health importance due to the presence of salt spas and resorts.

Now that you know what are salt flats and how they are formed, you may want to know how the salinization of aquifers can occur.

If you want to read similar articles to What Are Salt Flats and How Are They Formed?, we recommend you visit our Environment (other) category.