Geology
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To understand the rocks that make up the cliffs and gorge walls of the Palmiet Nature Reserve it is necessary to think in terms of a very different environment than exists today. The Natal Group, to which these sandstones belong, was formed about 600 million years ago. Well known geographical features such as the Drakensberg and Cape Mountains were still to be formed. KwaZulu-Natal lay near the heart of the supercontinent Gondwanaland (the Indian and Atlantic Oceans had not been formed).Animal life was only just beginning to evolve in the warm seas and plants had yet to colonise the land.
The Palmiet area and most of KwaZulu-Natal, must have resembled a desert similier toGobi Desert in China which is cold and arid. The total lack of plants (other than algae) and animals made the region much harsher than any modern equivalent and the climate one of even greater extremes. There were no soils and vegetation to retain water, and even the atmosphere was different, being richer in carbon dioxide and containing less oxygen.
So; envisage a long, flat-bottomed, sand-filled valley stretching from a major lake or inland sea near Port Shepstone, north-eastwards to a mountainous area in what is now southern Swaziland. Along the western edge of this valley (by Pietermaritzburg) barren rolling hills rose and stretched away to the far distance. On the eastern margin, which lay out past the present-day coast, similar hills stretched several hundreds of kilometres to the area that is now the Antarctic. A large river drained the highlands to the north east and smaller tributaries flowed in from both margins. However, as there was no soil or vegetation to form wetlands and retain water, the flow rate and river level was highly variable. When rains fell in the highland or hilly margins there was rapid runoff causing flash-floods to sweep down the valley, scouring out new river channels during peak discharge and depositing sheets of sandy alluvium after the flood. These layers of sand, now converted to sandstone, preserve the ripple marks and cross bedding caused by the flowing water during their deposition. During major floods the mass of water also caused movement in the layers of sand in the river bed, distorting the fine structures and sometimes folding and deforming the bedding. The sequence of events during each flood followed a very similar pattern. First the water would sweep down the almost dry, or slowly flowing, river bed washing away obstacles and often cutting new channels. As the power of the flood waters waned, first the coarsest sediment (pebbles and coarse sand), then progressively finer and finer material was deposited, so that in most sandstone beds the grain size systematically decreases from bottom to top. Although most of the material carried by the rivers was sand and gravel, after the floods some pools of muddy water remained. The mud settled in these ponds to form lens-shaped bodies of mudstone and siltstone while some ponds evaporated completely producing mudflakes, just like those formed when modern puddles dry out. In most cases the next flood eroded and destroyed the mud layers before depositing another bed of sand, but occasionally a mudstone layer was preserved, or the mudflakes survived long enough to be incorporated into sandstone beds. Often river channels filled with sand during repeated minor floods, so that during the stronger floods the river would overflow and cut new channels through the layers of sand.

This environment existed for many millions of years, with movement along fault lines at each side of the valley allowing the base of the valley to sink so that the several hundreds of metres of sand and pebbles accumulated, and were converted into rock by burial. However, during this time continental drift was slowly moving the supercontintent Gondwanaland towards the South Pole. The climatic change generated glaciers in the highlands, which steadily grew until about 350 million years ago Arctic conditions prevailed. At this stage the landscape must have appeared as a wasteland of snow and ice, much like southern Greenland or Ellsworth Land (Antarctica), with only the tops of a few rocky hills (nunataks) peeping through the ice.
During the cooling and initial glaciation much of the Natal Group was eroded as the debris-rich ice sheets scoured the country side. This erosive phase formed glacial pavements, such as the one in the University of Durban-Westville, and the scratch marks made by boulders frozen in the base of the glacier clearly indicate the direction of ice movement. Continental drift finally carried the area past the pole and into slightly warmer climates where the eroded debris could accumulate at the base of the glacier. In some parts of KwaZulu-Natal there is evidence that this glacial debris, termed the Dwyka Group, was reworked by flowing water, but in the Palmiet Nature Reserve area the mass of blue-grey rock containing many exotic pebbles and boulders is unsorted.
Although the deposition of the Dwyka Group marked the start of a major geological episode called the Karoo Era, in which many hundreds of metres of sediment accumulated, there is virtually no evidence of this phase in the Palmiet area. Only when the Gondwanaland began to break up some 200 million years ago did geological events again impact on the nature reserve. At this time the rocks that are now exposed on the land surface were far underground, and magma from deep in the earth (about 20 km) was able to escape upwards along the fractures in the splitting continent. Much of the magma escaped onto the surface to form the basaltic lava's, remnants of which are preserved in the Drakensberg and Lebombo region, but some was trapped in the fractures where it solidified to form dolomite. Occasionally fragments of sediments were caught up in the flow of magma and these xenoliths (fragment of rock differing in origion composition structure etc from the rock surrounding it}were altered to granite-like lumps by the heat of the magma.
After the initial deep-seated fracturing that split Gondwana into the African, Australian, Antarctic and Indian continents, there was a prolonged period of seismic activity as thecontinents adjusted to the new configuration. In the upper crust vertical and lateral movement occurred along fracture planes known as faults to compensate for mass movement. The fractured rock along the faults, called breccia, provided a pathway for the circulation of ground water. This ground water carried dissolved minerals, most commonly quartz, which were deposited in the breccia and associated fractures. In many cases the breccia was cemented by the minerals deposit or the fracture completely filled to form a vein, but in some cases the cavities were not completely filled and crystals can be found.
The geological history of the Palmiet Nature Reserve during the last 10 million years is one of erosion and the development of the various African Land Surfaces. However, in the most recent 50 000 years there have been dramatic changes in sea level related to the Ice Age. The massive sea level drop to about 120 m below the present level approximately 20 000 years ago caused the rivers meandering across the flat land surface to cut down in to the plain. The sudden increase in gradient, due to the change in sea level, combined with higher than present rainfall caused the rivers to cut down into their existing channels creating a pattern of incised meanders, and not the straighter lines associated with young or high gradient drainage patterns.
Thus, the topographic features visible today, whereby a relatively small river occupies a very deep and highly sinuous valley is a curious combination of both the rocks formed many millions of years ago and the events of relatively recent geological history.
Prof John Dunlevey

 

Palmiet Archaeological Sites

A COMMUNITY BASED EDUCATIONAL PROJECT -
EMPHASISING CULTURAL HERITAGE

AIMS

  • To provide an authentic archaeological dig and interpretation thereof at the PNR for viewing by scholars, visitors and tourists.
  • To provide a mock dig at the Bergtheil museum that echoes the archaeological finds at the PNR whereby hands-on educational programs can take place regarding the prehistory of the local area and how it fits into the greater puzzle of South African, African and world prehistory.
  • To create a visual recording of the process of the archaeological dig for the historic record with a view to creating a visual aid (video) for educational purposes.
  • To provide employment opportunities for the community through educational programs linked to the Palmiet archaeological dig and the mock dig at the Bergtheil museum.

PALMIET NATURE RESERVE ARCHAEOLOGY
AND BERGTHEIL MUSEUM WESTVILLE

Artefacts found in the PNR have been housed at the Bergtheil museum. These include Middle Stone Age artefacts, bored stones that have been linked to Late Stone Age and grinding stones and pottery shards that are associated with both Early and Late Iron Ages. The artefacts have been used for educational programs run by the museum and those initiated by a non-profit organisation, The Circle Connection.

Amafa, the heritage council for Kwa-Zulu Natal was approached by Mary Lange, of The Circle Connection, and Alvine Calboutin, curator of the Museum. Archaeologist, Annie van de Venter of Amafa came to the PNR and confirmed that it would be suitable as an educational archaeological site once a dig and interpretation had been executed.

Themba Zwane, an Amafa archaeologist, after a preliminary test pit offered to continue with the project on a voluntary basis. This he has done with the help of other volunteers.

CONCLUSION

The Palmiet prehistoric artefacts have, with other archaeological finds in the Highway/Cato Manor area, formed a collection of tangible prehistoric heritage important for educational purposes for school learners and educators The PNR could serve as an ideal location for outdoor learning and tourism. Not only could Learners and visitors read and hear about the living areas of the Early Stone and Iron Age inhabitants but would be able to experience early man’s environment. The Palmiet vegetation is also a unique visual aid to learners regarding the geological history of the area and the greater Durban and Kwa-Zulu Natal region.

There is in Westville the opportunity to create a unique heritage project that will provide cultural upliftment, empowerment, educational and tourism opportunities. This project would be the result of a co-operative association of; Government heritage agents such as Amafa KZN and the Bergtheil Museum, community cultural and heritage organisations such as The PNR Management Committee, The Circle Connection, the business sector, guides and educational assistants from the community.

The project could facilitate educational programs using local heritage to promote critical thinking.

September 2005 Update
We have cleared two squares up to 15 cm below surface.Finds in the first ten centimetres below the surface were the usual washdown and picnicing visitors i.e. charcoal, glass etc.The first historical cultural level has been reached in one of the squares which yielded old thick green tinted glass, a china sherd, some interesting shells and charcoal. Investigations continue to determine if the shelter was used during the South African Ango Boer War.  This cultural level has been linked to the period due to dating of the castle lager stopper plus a bullet casing.  Some coins have yet to be identified.

Steve Butler Palmiet Manager felt the site was unlikely to have been used in the winters as it is very cold with frost and no sun. In Pre Settler times it would have been exposed with grass land compared to its present wooded state. Archaeologists Themba Zwane and Gavin Whitelaw suspect that it was due to habitation during a time of conflict -we hope further excavation especially of the 60 to 70 cm below surface cultural level will add more evidence to this debate.

Palmiet Nature Reserve12 Jan 2005
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Map showing Greater Durban area

Evidence of a bygone era Photo Clive Read Mar 2003

 

 

 

Palmiet River Photo Clive Read 2003

 

 

 

 

The webmaster Clive Read ponders how all these rocks got here. March 2003

 

 

 

 

Palmiet Rock face Photo Clive Read

Themba Zwane

 

 

 

Themba Zwane and Mary Lange Aug 03

 

 

20 March 2004 Seems like Sa's favourite brew was popular in the thirties. Photo Clive Read

 

 

20 March 2004 Photo Clive Read