[AHW35-P07] Hydrochemical characteristics and sources of brines in the Sua Pans, Botswana.
Keywords:hydrochemical characteristics, origin of brines, Sua pans
A total of 39 brine, well and river samples were collected. Physical parameters of the samples such as electrical conductivity, pH, Temperature and salinity were also studied. Water temperatures on sampling varied between 23.8 and 29oC across the pans. The TDS concentration is highest 118400 ppm (mxw028) at the northeastern and within the pan. The TDS concentration is decreased to 41.28ppm (mxw011) at the wells between Ntwetwe pan and Sua pans outside the main wellfield. The lowest EC value was from borehole Mxw011 located on the western side of the project area. The vegetation is also more prominent in this area, indicating the potential for a perennially sustained freshwater regime. To a greater or lesser extent, the boreholes outside the pan reveal relatively fresh (or less saline) water overlying stronger saline water as observed from salinity profiling of monitoring boreholes. Major and minor elements were analyzed using Inductively Coupled Plasma–Atomic Emission Spectrometry (ICP–OES) and ion chromatography.