Variations in ⁸⁷Sr/⁸⁶Sr of the Huanxian profile, Loess Plateau of China from 40 ka B.P. to 10 ka B.P. and Heinrich events

Abstract

⁸⁷Sr/⁸⁶Sr ratios of acid-washed residues of the loess and paleosols since 40 ka B.P. from the Huanxian profile of the Loess Plateau, China, were determined. The investigation shows that ⁸⁷Sr/⁸⁶Sr ratios of the residues from the loess levels are generally lower than those from the paleosol levels. It is thought that the paleosol contain a higher proportion of the fine grain size parts (<2 um) than the loess. A correlation occurs among the variations in ⁸⁷Sr/⁸⁶Sr ratios, Zr/Rb ratios and mean grain size and, collectively they, imply that the East Asian winter monsoon was weak about from 40 ka B.P. to 30 ka, but it became stronger from about 30 ka B.P. to 10 ka B.P. Heinrich events of the North Atlantic region and Greenland correspond well to low ⁸⁷Sr/⁸⁶Sr ratios of residues of the Huanxian profile, which demonstrates that Heinrich events also influnced the east Asian region, including the Loess Plateau of China, and ⁸⁷Sr/⁸⁶Sr ratios of residues of the Loess Plateau can record information on high-frequency oscillations of the east Asian winter monsoon strength.