Cosmogenic Be ages on the Pomeranian Moraine, Poland
نویسندگان
چکیده
We measured the Be concentrations in boulders collected from the Pomeranian Moraine in Poland, providing the first direct dating of the southern margin of the Scandinavian Ice Sheet (SIS) in the Polish Lowland. The mean age of 8 Be ages of the Pomeranian Moraine in northwestern Poland is 14.3+0.8 Be ka, while in northeastern Poland the mean age of 19 Be ages of the moraine is 15.0+0.5 Be ka. Given the excellent agreement between the two age groups, we calculate a mean age of 14.8+0.4 Be ka for final deposition of the Pomeranian Moraine of northern Poland. The age of the Pomeranian Moraine suggests that the southern margin of the SIS was near its maximum extent in Poland at a younger time than previously inferred, and that retreat from the moraine at 14.8+0.4 Be ka probably occurred in response to the onset of the Bølling interstade.
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