The origin of the well-preserved, 1.13-km-diameter Pretoria Saltpan crater in South Africa has been debated throughout this century. The structure of this Pleistocene crater resembles that of other simple, bowl-shaped impact craters, but the presence of volcanic intrusive rocks along the crater rim has suggested a cryptovolcanic origin. In 1989 a drill core from the crater became available. The core was studied in detail to establish a paleoenvironmental record for the mid-latitudes of the Southern Hemisphere by analyzing the undisturbed crater sediments that had accumulated since formation of the crater, and to determine the origin of the crater. The discovery of shock-metamorphosed quartz and feldspar fragments, melt breccia and siderophile element-enriched glasses, and sulfide spherules in crater breccia deposits provides clear evidence for the impact origin of the Pretoria Saltpan crater.

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