Laguna del Negro Francisco

Laguna del Negro Francisco
Laguna del Negro Francisco
Location	Atacama Region
Coordinates	27°28′S 69°14′W / 27.467°S 69.233°W / -27.467; -69.233[1]
Catchment area	930 square kilometres (360 sq mi)
Basin countries	Chile
Surface area	20.7 square kilometres (8.0 sq mi)
Average depth	1 metre (3 ft 3 in)
Surface elevation	4,125 metres (13,533 ft)

Laguna del Negro Francisco is a lake in the Atacama Region of Chile and the southernmost closed lake in the country. It is situated 200 kilometres (120 mi) northeast of the city of Copiapó. The lake is about 10 kilometres (6.2 mi) long and 4 kilometres (2.5 mi) wide with a surface area of about 20.7 square kilometres (8.0 sq mi) and a depth of about 1 metre (3 ft 3 in). A peninsula, probably formed by a moraine and subsequently modified by wind-driven accumulation of sand, separates the lake into a north-northwesterly and a south-southeasterly half with different colour and water composition.

The lake is of tectonic origin and lies within a basin bordered by mountain ranges to the east and the west and two volcanoes north and south. It formed when the Astaburuaga River was redirected into the lake basin from the east, and this river is also its main source of water. Water levels have fluctuated over the last 6,000 years and the lake is currently in a period of low water level. In 1996 the lake was classified as a Ramsar site and it currently lies within the Nevado Tres Cruces National Park. In the past there were plans to redirect water flowing into the lake to the Copiapó River; presently a mining company holds water rights to the Astaburuaga River.