Evaluating the rate of rock art deterioration in the uKhahlamba-Drakensberg Park, KwaZulu-Natal

Abstract

One of the key reasons for the uKhahlamba‐Drakensberg Park’s status as a World Heritage Sites due is the abundance of rock art there. Unfortunately, through time, much of the rock art heritage in the Park is being lost through natural rock weathering processes, the decay of pigments and through the actions of people. The fragile art heritage is non‐renewable and, therefore, requires specialized management. In a case study, specific San paintings from Battle Cave study area were analysed using scanned and digital photographs with Geographic Information Systems software. Older images were compared with more recent ones and this was utilised to classify pigment colours and quantify the amount of deterioration that has taken place overtime. Various methodologies were applied to classifying the images, and it was found that manual digitising provided the best means for quantifying the amount of deterioration. A detailed analysis was undertaken of a feline painting at Battle Cave, as it had the best quality images that could be dated. Results showed that white pigment in the painting degraded more rapidly than the ochre colours. Visual analysis suggests that the damage to the figure is predominantly through pigment decay and through the granular disaggregation of the rock surface. Where pigments were applied to what were clearly weathered rock surfaces, the change was greatest over the 40‐year intervening period between images analysed. The methodology utilised in this study can be utilised to evaluate the rate of decay of rock art and is, therefore a useful tool for determining priorities with regard to the conservation of San paintings. In addition, the rate of deterioration is useful for evaluating and quantifying the contribution of rock weathering to landscape evolution. Copyright