The Cenozoic Kalahari Basin covers large parts of southern Africa. A continuous 400 m core was obtained in northern Namibia and analyzed in detail. Here, we present sedimentological, geochemical, mineralogical, granulometric, and hydraulic data, which were used to derive the sedimentation history and the Cenozoic paleoclimate and paleogeography of SW Africa. The first absolute ages for the Kalahari Basin were obtained by dating of calcretes, which showed that the core covers almost the entire Cenozoic. Two megafans could be distinguished. The older, buried Olukonda Megafan stems from a mafic source rock, potentially the Kunene Intrusive Complex, and was deposited by a paleo–Kunene River towards the southeast and east, under a semiarid climate. The younger Cubango Megafan (Andoni Formation) has a completely different provenance, namely felsic metamorphic and granitoid rocks, transported from the north by the Cubango River. The capture of the Kunene towards the Atlantic during the Eocene resulted in this change in provenance. Despite the distinct differences between the formations, the temporal hiatus between them must have been short. The results are a showcase of the potential of megafans for hosting major deep freshwater aquifers.

中文翻译：

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喀拉哈里盆地堆积的巨扇，作为非洲西南地区的古地理，河流捕获和新生代古气候档案

新生代卡拉哈里盆地覆盖了南部非洲的大部分地区。在纳米比亚北部获得了连续的400 m岩心，并进行了详细分析。在这里，我们介绍了沉积学，地球化学，矿物学，粒度学和水力数据，这些数据用于推导非洲西南部的沉积历史以及新生代古气候和古地理。喀拉哈里盆地的第一个绝对年龄是通过对凝结岩进行测年获得的，这表明岩心几乎覆盖了整个新生代。可以区分两个超级粉丝。较老的埋藏的Olukonda Megafan来自镁铁质烃源岩，可能是Kunene侵入复合体，并在半干旱气候下由古-库内内河向东南和东部沉积。较年轻的Cubango Megafan（Andoni队）的出身完全不同，即长石质变质花岗岩体，由库班戈河从北部运出。在始新世期间，库内内（Kunene）被捕获到大西洋，导致了物源的这种变化。尽管编队之间存在明显差异，但它们之间的时间间隔一定很短。结果证明了巨型扇潜在地容纳主要的深层淡水含水层。