Don Juan Pond

Salzhaltigster lake in the world

The Don Juan Lake, Don Juan Pond is a small and very shallow hypersaline lake on the west end of Wright Valley ( South Fork ), Victoria Land, Antarctica, 9 km west of Vandasees. It's wedged between the Asgard Range ( Oliver Peak) in the south and the Dais in the north. At the western end there is a small tributary and a peculiarity that has been described as a rock glacier. The Don Juan lake is considered salzigstes waters of the earth with a salinity of about 40%.

The lake was discovered in 1961 and after two helicopter pilots, Lt. Don ( ald ) Roe and Lt John Hickey, named, who flew the helicopter the first investigation of the water. In this first investigation ruled temperatures of -30 ° C and the highly saline water was still in the liquid state.

Salinity

The Don Juan Lake is a shallow hypersaline lake with a flat bottom. He has a higher salinity than the Dead Sea and Lake Assal in Djibouti as the.

The lake is described as a groundwater discharge zone. The dominant ions in the solution are calcium ions and chloride ions. The area around the Don Juan Lake is covered with sodium chloride and calcium chloride salts that are left behind when the water evaporates. The area and volume of the Don Juan Lake fluctuate over time. According to the " USGS topo map" of 1977 its area was around 0.25 km ². Apparently, however, the size of the lake has shrunk considerably in recent years. The maximum depth in 1993-94 was described as " a foot deep " (about 30 cm). In January 1997, there were about 10 cm and in December 1998 the lake to an area of ​​a few tens of square meters was almost dry. Most of the water that was left was limited to sink close to large boulders in the lake.

The calculated composition of the water is CaCl 2 3.72 mol / kg of NaCl and 0.50 mole / kg. This solution only freezes at a temperature of -51.8 ° C. This corresponds to 413 g of CaCl2 and 29 g NaCl per kg of water (about 44.2 %).

The Don Juan Lake is the type locality of the rare mineral Antarcticite, a hydrous calcium chloride.