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Pollen analyses and radiocarbon dates from the bottom sediments in the Kaali main crater suggested that the crater group is at least 4000?C5000 years old. Investigations of silicate impact micro-spherules in surrounding mires (Raukas et al. 1995) put the age about 7500?C7600 yr BP. Recently we found both silicate and iron microspherules from organic sediments below well-dated beach ridge in Reo site what supports the conclusions that the most realistic age of the Kaali craters is 7600±50 14C BP (8335?C8537 cal BP) and the meteorite fall was from SSE to NNW.  相似文献   
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