Nooitgedacht Glacial Pavements
Encyclopedia
The Nooitgedacht Glacial Pavements comprise a geological feature between Kimberley
Kimberley, Northern Cape
Kimberley is a city in South Africa, and the capital of the Northern Cape. It is located near the confluence of the Vaal and Orange Rivers. The town has considerable historical significance due its diamond mining past and siege during the Second Boer War...

 and Barkly West, South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

, pertaining to the Palaeozoic-age Dwyka
Dwyka
Dwyka is the name of a river in the Karoo in South Africa, adopted by geologists to define the Karoo Ice Age some 300 million years ago. Key sites in South Africa show evidence of glaciation, including Nooitgedacht near Kimberley. In South Africa, near the South Pole at that time as a result of...

 Ice Age, or Karoo Ice Age
Karoo Ice Age
The Karoo Ice Age from 360–260 Ma was the second major ice age of the Phanerozoic Eon. It is named after the glacial tills found in the Karoo region of South Africa where evidence for this ice age was first clearly identified....

, (some 300 million years ago) where the glacially scoured (smoothed and striated) ancient bedrock (re-exposed by erosion) was used, substantially more recently, during the Later Stone Age period in the late Holocene
Holocene
The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...

 as panels for rock engravings.

Ice Age

Some 300-290 million years ago, during Dwyka
Dwyka
Dwyka is the name of a river in the Karoo in South Africa, adopted by geologists to define the Karoo Ice Age some 300 million years ago. Key sites in South Africa show evidence of glaciation, including Nooitgedacht near Kimberley. In South Africa, near the South Pole at that time as a result of...

 times, what is now Southern Africa
Southern Africa
Southern Africa is the southernmost region of the African continent, variably defined by geography or geopolitics. Within the region are numerous territories, including the Republic of South Africa ; nowadays, the simpler term South Africa is generally reserved for the country in English.-UN...

 was, as a result of plate tectonics
Plate tectonics
Plate tectonics is a scientific theory that describes the large scale motions of Earth's lithosphere...

, near the South Pole
South Pole
The South Pole, also known as the Geographic South Pole or Terrestrial South Pole, is one of the two points where the Earth's axis of rotation intersects its surface. It is the southernmost point on the surface of the Earth and lies on the opposite side of the Earth from the North Pole...

 and large ice sheets or glaciers covered high-lying areas. Geologists term this upland the Cargonian Highlands, stretching from what is now the Northern Cape
Northern Cape
The Northern Cape is the largest and most sparsely populated province of South Africa. It was created in 1994 when the Cape Province was split up. Its capital is Kimberley. It includes the Kalahari Gemsbok National Park, part of an international park shared with Botswana...

 through Gauteng
Gauteng
Gauteng is one of the nine provinces of South Africa. It was formed from part of the old Transvaal Province after South Africa's first all-race elections on 27 April 1994...

 to Mpumalanga
Mpumalanga
Mpumalanga , is a province of South Africa. The name means east or literally "the place where the sun rises" in Swazi, Xhosa, Ndebele and Zulu. Mpumalanga lies in eastern South Africa, north of KwaZulu-Natal and bordering Swaziland and Mozambique. It constitutes 6.5% of South Africa's land area...

. As the Dwyka glaciers moved, grinding their way southwards, the rocks and rubble that became embedded in their belly smoothed the underlying Andesite
Andesite
Andesite is an extrusive igneous, volcanic rock, of intermediate composition, with aphanitic to porphyritic texture. In a general sense, it is the intermediate type between basalt and dacite. The mineral assemblage is typically dominated by plagioclase plus pyroxene and/or hornblende. Magnetite,...

 rock pavements and scoured out scratch marks, known as striations. As the ice shaped the landscape, the continent of Gondwanaland continued to drift slowly northwards, ultimately bringing this area into warmer latitudes. As the glaciers melted, a mixture of clay and rock was left behind which eventually consolidated into a rock called Tillite – the lower-most layer in the Karoo sequence. Quite large erratics or drop stones carried here by glacial action are found at Nooitgedacht. The changing local environment also created conditions conducive for the burgeoning of life, reflected in the rich fossil record of the Karoo.

River of diamonds

Along this portion of its course, the adjacent Vaal River
Vaal River
The Vaal River is the largest tributary of the Orange River in South Africa. The river has its source in the Drakensberg mountains in Mpumalanga, east of Johannesburg and about 30 km north of Ermelo and only about 240 km from the Indian Ocean. It then flows westwards to its conjunction...

, and earlier generations of rivers and erosion processes, have cut through and swept away a vast mass of Karoo rock and sediment, to re-expose the volcanic Andesite landscape formed 2.7 billion years ago and shaped by glacial action 300 million years ago. At one time – when the diamondiferous pipes penetrated to the surface between 120 and 90 million years ago – it is estimated that about 1 km of Karoo sediment overlay the Kimberley-Barkly West area. Diamonds were eroded out of these pipes and caught in pockets of sediment and gravels which, once discovered, changed the course of modern South African history.

Since 1869 the various gravels along the Vaal River have been worked intensively for their content of high-grade alluvial diamonds. The Nooitgedacht diggings were opened in 1949 and closed in 1981. During these 32 years, a total of 80 000 diamonds were found here. The Venter Diamond, a 511 carats (102.2 g) yellow stone, was the largest.

The standard size of a digger's claim was 15 x 15 metres. The diamond-bearing gravels, covered by a layer of sterile red sand, were washed by hand in simple rotary pans. The left-over concentrate of heavy material was then carefully sorted for diamonds.

The search for diamonds continues along the Vaal River in the Windsorton, Barkly West and Delportshoop areas and further downstream.

Diggings on Nooitgedacht itself were opened again in the late 1990s.

Some small-scale diggers in the region still use pick and shovel to eke out a meagre return, but miners using heavy earth-moving equipment obtain far better results. The impacts of this on the environment and on heritage resources are not small.

Rock Art

The images found on the andesite glacial pavements at Nooitgedacht are a form of rock art called rock engravings (the term petroglyph is also sometimes used). They were produced by pecking out the outlines or silhouettes of animals, or ‘geometric’ designs, with a pointed stone (there is no evidence that the artists used metal tools, nor indeed diamonds). They were made by ancestors of San and Khoe people, probably during the past 1500 years. The engravings include depictions of humans, eland, rhinoceros, ostrich, giraffe and anteater. The more abstract forms may depict bags and aprons, as well as ‘geometric’ images such as are common at other sites in the region, particularly Driekops Eiland.

What these different images mean is subject to debate. One argument suggests that whereas sites such as the nearby Wildebeest Kuil, with its profusion of engravings of animals and some human figures, is quintessentially San/hunter-gatherer in character, sites such as Nooitgedacht and Driekops Eiland
Driekops Eiland
Driekops Eiland is a rock engraving or petroglyph site in the bed of the Riet River close to the town of Plooysburg, near Kimberley, Northern Cape, South Africa.-The engravings:...

, where geometric engravings occur in great numbers, may belong to a different tradition of rock art, a separate Khoekhoe herder rock art tradition. A different perspective does not discount this possibility, but questions whether assigning variability in terms of ethnic or cultural differences in the first instance does not overlook other possible factors.

Research at Driekops Eiland suggests that sites such as this, and the ‘geometric’ engravings, bags and aprons present, may have been produced as part of girls’ coming-of-age rites, potentially across the spectrum of both San and Khoekhoe contexts, given the similarities in beliefs and ritual practices.

Diamond Fields Land Dispute

Various claims and counter claims to ownership of this territory were made following the discovery of diamonds in 1869-70. Nooitgedacht featured early on, when the Presidents of the Free State
Free State
The Free State is a province of South Africa. Its capital is Bloemfontein, which is also South Africa's judicial capital. Its historical origins lie in the Orange Free State Boer republic and later Orange Free State Province. The current borders of the province date from 1994 when the Bantustans...

 and Transvaal
South African Republic
The South African Republic , often informally known as the Transvaal Republic, was an independent Boer-ruled country in Southern Africa during the second half of the 19th century. Not to be confused with the present-day Republic of South Africa, it occupied the area later known as the South African...

 Republics met here with the Griqua Chief Waterboer and his agent David Arnot
David Arnot
David Arnot O. S. A. was a 16th century Scottish Augustinian abbot and bishop. He was from the Arnot family of Arnot, Fife.-Archdeacon of Lothian:...

, on 18 August 1870. The Griqua representatives walked out in a huff and the Free State proclaimed the territory theirs. But this was not the end of the story, the dispute being settled eventually by the Keate Award (in favour of Waterboer, who placed himself under British protection), and the proclamation of the Crown Colony of Griqualand West
Griqualand West
Griqualand West is an area of central South Africa with an area of 40,000 km² that now forms part of the Northern Cape Province. It was inhabited by the Griqua people - a semi-nomadic, Afrikaans-speaking nation of mixed-race origin, who established several states outside the expanding frontier...

on 27 October 1871.

Preservation as Heritage Site

The site was declared a National Monument in 1936 and under South Africa's Act 25 of 1999 is now a Grade 2 Provincial Heritage Site.

External links

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