Deposition of sediments in the Karoo basin of southern Africa in a semiarid and later an arid environment has resulted in the formation of Molteno, Elliot and Clarens Formations. Subsequent igneous intrusions of dolerites that resulted in the outflow of the Drakensberg volcanic lavas through these Late Triassic and Early Jurassic sandstones has helped form a remarkable landscape with shear faces in deeply incised river valleys. It is proposed that the shear faces are the result of low weathering rates in resistant sandstone that has been metamorphosed adjacent to the volcanic intrusions. Throughout the Clarens Formation of KwaZulu-Natal, the deep incision of rivers has exposed less resistant sediments below desert dune deposits of the upper Karoo sandstones. The fluvially deposited sandstones, mudstones and siltstones the lower parts of the Clarens Formation have weathered and eroded at a quicker rate than those above, resulting in the formation of characteristic rock overhangs. The numerous rock overhangs that gave the Clarens Formation its original name of Cave Sandstone, provided shelter for the indigenous hunter gatherers, the Bushman or San people who inhabited the interior of southern Africa for at least 25 000 years until the late 19th Century . The relatively porous sandstones in the rock shelters and on isolated boulders provided an ideal canvas for San to paint scenes that reflected their history and spirituality. It is said that Clarens Formation sandstones contain amongst the highest the highest concentrations of rock paintings in the world. The San hunter-gatherers, although now extinct in much of southern Africa, have left behind a valuable World heritage through their paintings and engravings.

Unfortunately, through time, much of the rock art heritage in the Drakensberg and adjacent mountains of southern Africa is being lost through natural rock weathering processes, the decay of pigments and through vandalism by humans. The deterioration of San paintings in southern Africa was noted as early as the late Eighteenth Century in the south-western parts of the sub-continent . The deterioration of rock art was only recognised by earth scientists in the context of providing an estimation of the rate of relative weathering rates.

Despite an acknowledgement of the negative impact of rock weathering processes on San paintings, little has been achieved with regard to determining the processes of deterioration or techniques for the preservation indigenous rock art in southern Africa. The general lack of understanding concerning specific mechanisms of rock weathering is the major reason for inadequate research into rock art preservation in southern Africa. Most literature concerned with the deterioration of rock art as a result of rock weathering processes is speculative, qualitative and lacks the rigour required for an evaluation of the role of specific weathering processes.

Previous investigations by Ian Meiklejohn has provided the basis for further research, but this study is limited in terms of its application to a specific study area and a single lithology. The rock art heritage in southern Africa is vast and extends from the south-western regions of South Africa northwards into Namibia, Botswana, Zimbabwe and Malawi. Rock art has even recorded in central and east Africa and is particularly well documented in North Africa. Therefore, a need arises for extensive research to evaluate the mechanisms causing the decay of rock art, throughout southern Africa.