Basin Groundwater Hydrology The Groundwater Hydrology of the Okavango Basin FAO (2010) Internal Report prepared by MJ Jones (Consultant) for FAO April 2010 1 Basin Groundwater Hydrology TOC Contents 1 INTRODUCTION .......................................................................................................................... 5 2 GEOLOGICAL SETTING ............................................................................................................. 6 2.1 Tectonic Background .............................................................................................................. 6 2.2 The Karoo System ................................................................................................................... 7 2.3 Post Karoo Geological Events .............................................................................................. 14 2.4 The Post-Cretaceous development of the Okavango Basin .................................................. 18 2.5 The Kalahari Group .............................................................................................................. 20 2.6 The Lower Kalahari Group Formations ................................................................................ 20 2.7 The Kalahari Sands ............................................................................................................... 24 2.8 The Tectonic Development of the Okavango Graben ........................................................... 25 2.9 Impact of the Palaeo-geomorphological Legacy in the Okavango Basin ................................... 27 3 THE GROUNDWATER OCCURRENCES AND QUALITY IN THE OKAVANGO BASIN . 33 3.1 Potential Aquifer Recharge ................................................................................................... 33 3.2 Depth to Groundwater ........................................................................................................... 37 3.3 Groundwater Quality............................................................................................................. 37 4 HYDROGEOLOGICAL PROVINCES OF THE OKAVANGO BASIN .................................... 39 4.1 The Cubango-Cuito Basin ..................................................................................................... 39 4.2 The Omatako and Eiseb Basins ............................................................................................ 49 4.3 Ghanzi Block ........................................................................................................................ 51 4.4 The Okavango Delta ............................................................................................................. 53 4.5 Makgadikgadi Block ............................................................................................................. 56 4.6 Central Kalahari Block .......................................................................................................... 59 5 CONCLUSIONS ........................................................................................................................... 69 6 REFERRENCES ........................................................................................................................... 70 2 Basin Groundwater Hydrology Table of Figures Figure 1: .................................................................................................................................................. 6 Figure 2 ................................................................................................................................................... 7 Figure 3 ................................................................................................................................................... 7 Figure 4 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