Seven Coloured Earths
Encyclopedia
The Seven Coloured Earth(s) (Terres des Sept Couleurs in french
) are a geological formation and prominent tourist attraction
found in the Chamarel
plain, in the Black River District of south-western Mauritius
. It is a relatively small area of sand dunes comprising sand of seven distinct colours (approximately red, brown, violet, green, blue, purple and yellow). The main feature of the place is that since these differently coloured sands spontaneously settle in different layers, dunes acquire a surrealistic
, striped colouring. This phenomenon can also be observed, on a smaller scale, if one takes a handful of sands of different colours and mixes them together, as they'll eventually separate into a layered spectrum. Another interesting feature of Chamarel's Coloured Earths is that the dunes seemingly never erode
, in spite of Mauritius' torrential, tropical
rains.
The sands have formed from the decomposition of volcanic rock
(basalt
) gullies
into clay
, further transformed into ferralitic soil by total hydrolysis
; the two main elements of the resulting soil, iron
and aluminium
, are responsible for red/anthracite and blue/purplish colours respectively. The different shades of colour are believed to be a consequence of the molten volcanic rock cooling down at different external temperatures (hence rates), but the causes of their consistent spontaneous separation are yet to be fully clarified.
The place has become one of Mauritius' main tourist attractions since the 1960s
. Nowadays, the dunes are protected by a wooden fence and visitors are not allowed to climb on them, although they can look at the scenery from observation outposts placed along the fence. Curio shops in the area sell small test-tubes filled up with the coloured earths.
French language
French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...
) are a geological formation and prominent tourist attraction
Tourist attraction
A tourist attraction is a place of interest where tourists visit, typically for its inherent or exhibited cultural value, historical significance, natural or built beauty, or amusement opportunities....
found in the Chamarel
Chamarel
Chamarel is village in the southwest of Mauritius with a population of 700. It is is named after the frenchman Charles Antoine de Chazal de Chamarel, who lived in the area around 1800....
plain, in the Black River District of south-western Mauritius
Mauritius
Mauritius , officially the Republic of Mauritius is an island nation off the southeast coast of the African continent in the southwest Indian Ocean, about east of Madagascar...
. It is a relatively small area of sand dunes comprising sand of seven distinct colours (approximately red, brown, violet, green, blue, purple and yellow). The main feature of the place is that since these differently coloured sands spontaneously settle in different layers, dunes acquire a surrealistic
Surrealism
Surrealism is a cultural movement that began in the early 1920s, and is best known for the visual artworks and writings of the group members....
, striped colouring. This phenomenon can also be observed, on a smaller scale, if one takes a handful of sands of different colours and mixes them together, as they'll eventually separate into a layered spectrum. Another interesting feature of Chamarel's Coloured Earths is that the dunes seemingly never erode
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...
, in spite of Mauritius' torrential, tropical
Tropical climate
A tropical climate is a climate of the tropics. In the Köppen climate classification it is a non-arid climate in which all twelve months have mean temperatures above...
rains.
The sands have formed from the decomposition of volcanic rock
Volcanic rock
Volcanic rock is a rock formed from magma erupted from a volcano. In other words, it is an igneous rock of volcanic origin...
(basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
) gullies
Gully
A gully is a landform created by running water, eroding sharply into soil, typically on a hillside. Gullies resemble large ditches or small valleys, but are metres to tens of metres in depth and width...
into clay
Clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...
, further transformed into ferralitic soil by total hydrolysis
Hydrolysis
Hydrolysis is a chemical reaction during which molecules of water are split into hydrogen cations and hydroxide anions in the process of a chemical mechanism. It is the type of reaction that is used to break down certain polymers, especially those made by condensation polymerization...
; the two main elements of the resulting soil, iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
and aluminium
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
, are responsible for red/anthracite and blue/purplish colours respectively. The different shades of colour are believed to be a consequence of the molten volcanic rock cooling down at different external temperatures (hence rates), but the causes of their consistent spontaneous separation are yet to be fully clarified.
The place has become one of Mauritius' main tourist attractions since the 1960s
1960s
The 1960s was the decade that started on January 1, 1960, and ended on December 31, 1969. It was the seventh decade of the 20th century.The 1960s term also refers to an era more often called The Sixties, denoting the complex of inter-related cultural and political trends across the globe...
. Nowadays, the dunes are protected by a wooden fence and visitors are not allowed to climb on them, although they can look at the scenery from observation outposts placed along the fence. Curio shops in the area sell small test-tubes filled up with the coloured earths.