Gaet'ale Pond is a small

hypersaline lake A hypersaline lake is a landlocked body of water that contains significant concentrations of sodium chloride, brines, and other salts, with saline levels surpassing that of ocean water (3.5%, i.e. ). Specific microbial species can thrive in ...

located near the Dallol crater in the

Danakil Depression The Danakil Depression is the northern part of the Afar Triangle or Afar Depression in Ethiopia, a geological depression that has resulted from the divergence of three tectonic plates in the Horn of Africa. Geology The Danakil Depression lies ...

(

Afar Region The Afar Region (; aa, Qafar Rakaakayak; am, አፋር ክልል), formerly known as Region 2, is a regional state in northeastern Ethiopia and the homeland of the Afar people. Its capital is the planned city of Semera, which lies on the paved ...

, Ethiopia). It is located over a

hot spring A hot spring, hydrothermal spring, or geothermal spring is a spring produced by the emergence of geothermally heated groundwater onto the surface of the Earth. The groundwater is heated either by shallow bodies of magma (molten rock) or by circ ...

of tectonic origin and has no apparent inlet or outlet streams. The water of Gaet'ale Pond has a

salinity Salinity () is the saltiness or amount of salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal ...

of 43%, making it the saltiest water body on Earth.

Location and origin

Gaet'ale Pond is the largest of a series of small ponds located approximately southeast of Dallol springs. It is crescent-shaped with a diameter of about . According to residents of the nearby village of Ahmed'ela, an earthquake in January 2005 reactivated a thermal spring and the pond was created. For this reason, its temperature of is hotter than the environment.

Composition of the water

The salts in the water of Gaet'ale Pond are mainly composed by

calcium chloride Calcium chloride is an inorganic compound, a salt with the chemical formula . It is a white crystalline solid at room temperature, and it is highly soluble in water. It can be created by neutralising hydrochloric acid with calcium hydroxide. Ca ...

at 2.72 mol/kg and

magnesium chloride Magnesium chloride is the family of inorganic compounds with the formula , where x can range from 0 to 12. These salts are colorless or white solids that are highly soluble in water. These compounds and their solutions, both of which occur in natu ...

at 1.43 mol/kg. It also contains small amounts of Na⁺, K⁺ and NO₂⁻ ions. The total amount of dissolved solids content is 433 g/kg, or 43.3%. It also contains traces of

iron(III) In chemistry, iron(III) refers to the chemical element, element iron in its +3 oxidation number, oxidation state. In salt (chemistry), ionic compounds (salts), such an atom may occur as a separate cation (positive ion) denoted by Fe3+. The adjec ...

that form a complex with

chloride The chloride ion is the anion (negatively charged ion) Cl−. It is formed when the element chlorine (a halogen) gains an electron or when a compound such as hydrogen chloride is dissolved in water or other polar solvents. Chloride salts ...

, giving the water a characteristic yellow color. Bubbles of odourless gas are emitted from the lake surface. It is likely volcanically produced

carbon dioxide Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transpar ...

. Bird and insect corpses have been found around the pond, and it has been proposed that the gas may be harmful for small animals or humans.

References

External links

{{portal, Lakes
Hyperdiverse archaea near life limits at the polyextreme geothermal Dallol area
Bodies of water of Ethiopia Afar Region Ponds of Africa Saline lakes of the Great Rift Valley 2008 beginnings