Don Juan Pond

Don Juan Pond is located in the west end of the Wright Valley. It is wedged between the Asgard Range and the Dias. On the west end there is a small tributary and a feature that has been described as a rock glacier. Don Juan Pond is a shallow (i.e. flat bottom) hyper-saline pond. The salinity is high enough that it doesn't freeze even in winter. Therefore, unlike other lakes and ponds in the dry valleys, it has no ice cover. It has been described as a groundwater discharge zone. The dominant ions in solution are calcium and chloride. The area around Don Juan Pond is covered with sodium chloride and calcium chloride salts that have been precipitated as the water evaporated. Area and volume of Don Juan Pond varies over time. According to the USGS topo map published in 1977, the area was approximately 0.25 sq. km. However, in recent years the size of the pond has shrunk considerably. The pond has changed over the past 5 years although this is mostly anecdotal. The maximum depth in 93-94 was described as "a foot deep." In Jan 97, it was approximately 10cm deep; in Dec 98 the pond was almost dry everywhere except for an area 10's of sq meters. Most of the water that was left was restricted to depressions around large boulders in the pond. Valley: Wright Distance to Sea : 60 Maximum Length (km): 0.75 Maximum Width (km): 0.35 Maximum Depth (m): 0.1

Coordinates:

Latitude: -77.561897277832
Longitude: 161.190994262695