Sinkholes are subsidence or collapse features that form at points of local instability and are usually associated with dolomite or karst landscapes.
Sinkholes form as a result of subsurface subsidence which result in surface depressions. These features can range from tens to hundreds of meters in extent. While generally associated with karstic landscapes, they are also common in intensely mined areas in South Africa.
Why are sinkholes important?
Sinkholes are unstable areas which pose a risk to communities around them, are vulnerable points through which contamination can enter the subsurface, promote enhanced recharge and can form attractive surface water features used for recreational or water supply purposes.