PALEOCLIMATE SIGNALS OF LAKE HOVSGOL, MONGOLIA, OVER THE LAST 19,000 YEARS USING AUTHIGENIC BERYLLIUM ISOTOPES

초록

The paleoclimatic signal of Lake Hovsgol in Mongolia was investigated using authigenic beryllium isotopes from 20 sediment samples. The beryllium isotopic records from this study indicate that there were three dry and cold periods at the lake around 9400, 12,700, and 17,100 cal yr BP. The significant Be-10 signal during the Younger Dryas (YD) period is found to be lower. This indicates that the Lake Hovsgol area was subject to a period of cold and dry conditions with minimal dust input, which manifests itself as a low Be-9 profile in this study. In warmer and wetter climatic conditions, the Be-10 concentration was found to be higher, and this agrees with the sedimentation record of this study. The climatic signals from Lake Hovsgol appear to be similar to a decreased beryllium record during the deglacial period. The results of this study confirm that the Lake Hovsgol area also experienced the global paleoclimatic change associated with the YD event around 12,700 cal yr BP. Further investigation using worldwide lake records by the analytical technique of authigenic beryllium will be useful for understanding the global paleoclimatic change pattern in conjunction with lake-level change.

키워드