Multispectral satellite imagery was used to map surficial features (regolith) by delineating differences in the spectral reflectance properties of different surficial materials. Borehole lithological logs were then used to validate the surficial interpretation. In terms of potential aquifers in Kalahari Sediments, the interpreted surficial features were classified into four hydro-lithological classes: alluvium, delta sediments, Kalahari Sands, pan and lacustrine sediments. Existing borehole data comprising of lithological logs, borehole yield, depth to water strikes, groundwater levels, total dissolved solids (TDS) were then assigned to the different hydro-lithological units. These data sets were then used to interpolate aquifer productivity and water quality distribution (TDS) for each hydro-lithological unit in the study.
NOTE;This groundwater resources potential map is produced to illustrate the groundwater potential of the area and potential groundwater quality based on best available (existing) borehole data for planning purposes. Primarily it indicates potential aquifer productivity, potential groundwater quality, depth to first water strikes and groundwater flow directions in generalized terms. Thus the map provides information of a regional nature on the known aquifers in the area. This map should assist planners and developers in selecting those areas most favourable for groundwater development but it cannot be considered suitable for local borehole siting purposes.
