Karst Risk Map of Nova Scotia

A sinkhole is a natural depression or hole in the Earth's surface which may have various causes. Most natural sinkholes are caused by the chemical dissolution of water-soluble carbonate rocks or gypsum. Sinkholes may vary in size from 1 to 600 m both in diameter and depth. Sinkholes may be formed gradually or by sudden collapse and are found worldwide in ‘karst areas.’ Karst areas are not unique to Nova Scotia; in fact, they occur in over a quarter of the earth’s surface. As a result, there are well-established methods for reducing karst risks. These include actions that can be taken both at the planning and construction stage of a project, as well as on-going actions that reduce the risk of future sinkhole formation. This dataset was developed to show areas of Nova Scotia where there is a relatively high-medium-low risk of encountering karst and naturally occurring sinkholes caused by soluble bedrock.