Tswaing crater
Encyclopedia
Tswaing is an impact crater
in South Africa. This astrobleme is 1.13 km in diameter and 100 m deep and the age is estimated to be 220,000 ± 52,000 years (Pleistocene
). The impactor is believed to have been a chondrite
or stony meteorite some 30 to 50 m in diameter that was vaporized during the impact event.
The name Tswaing means Place of Salt in Tswana
and the crater was also formerly known in as Pretoria Saltpan crater and in . Stone tools from the Middle Stone Age
show that the crater was regularly visited by people from as far back as 100,000 years ago in order to hunt and collect salt. Water in the crater comes from surface springs, ground water and rain water and is rich in dissolved carbonates and sodium chloride
s. Tswana and Sotho people harvested the salt by filtering and decoction
between 1200 and 1800. Between 1912 and 1956 brine was pumped from the floor of the crater by the company SA Alkali Ltd. in order to extract soda and salt.
Tswaing is currently on the tentative list for consideration as a World Heritage Site
.
Impact crater
In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...
in South Africa. This astrobleme is 1.13 km in diameter and 100 m deep and the age is estimated to be 220,000 ± 52,000 years (Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
). The impactor is believed to have been a chondrite
Chondrite
Chondrites are stony meteorites that have not been modified due to melting or differentiation of the parent body. They formed when various types of dust and small grains that were present in the early solar system accreted to form primitive asteroids...
or stony meteorite some 30 to 50 m in diameter that was vaporized during the impact event.
The name Tswaing means Place of Salt in Tswana
Tswana language
Tswana or Setswana is a language spoken in Southern Africa by about 4.5 million people. It is a Bantu language belonging to the Niger–Congo language family within the Sotho languages branch of Zone S , and is closely related to the Northern- and Southern Sotho languages, as well as the Kgalagadi...
and the crater was also formerly known in as Pretoria Saltpan crater and in . Stone tools from the Middle Stone Age
Middle Stone Age
The Middle Stone Age was a period of African Prehistory between Early Stone Age and Late Stone Age. It is generally considered to have begun around 280,000 years ago and ended around 50-25,000 years ago. The beginnings of particular MSA stone tools have their origins as far back as 550-500,000...
show that the crater was regularly visited by people from as far back as 100,000 years ago in order to hunt and collect salt. Water in the crater comes from surface springs, ground water and rain water and is rich in dissolved carbonates and sodium chloride
Sodium chloride
Sodium chloride, also known as salt, common salt, table salt or halite, is an inorganic compound with the formula NaCl. Sodium chloride is the salt most responsible for the salinity of the ocean and of the extracellular fluid of many multicellular organisms...
s. Tswana and Sotho people harvested the salt by filtering and decoction
Decoction
Decoction is a method of extraction, by boiling, of dissolved chemicals, or herbal or plant material, which may include stems, roots, bark and rhizomes. Decoction involves first mashing, and then boiling in water to extract oils, volatile organic compounds, and other chemical substances...
between 1200 and 1800. Between 1912 and 1956 brine was pumped from the floor of the crater by the company SA Alkali Ltd. in order to extract soda and salt.
Tswaing is currently on the tentative list for consideration as a World Heritage Site
World Heritage Site
A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...
.
See also
- Impact eventImpact eventAn impact event is the collision of a large meteorite, asteroid, comet, or other celestial object with the Earth or another planet. Throughout recorded history, hundreds of minor impact events have been reported, with some occurrences causing deaths, injuries, property damage or other significant...
- List of impact craters in Africa