内蒙古伊克昭盟盐湖晚第四纪氧联同位素记录及古气候研究

根据内蒙古伊克昭盟５个盐湖中６个钻孔岩心的３４０件氧碳稳定同位素样品测试数据，分析了该区的古气候变化特征。氧碳同位素记录的研究表明，盐湖水体的δ１３Ｏ变化主要是受湖水的蒸发作用和淡化过程所控制，而δ１３Ｃ值的波动主要受湖泊水体中ＴＤＩＣ变化以及湖泊水体与大气间碳交换的制约。盐湖的水体环境在过去２３ｋａ之中经历了１７次明显的波动变化，揭示了晚更新世冷湿—早全新世暖湿—中晚全新世暖（偏冷）干的晚第四纪气俟变化规律及３个重要的气侯事件（１０．８０～１０．５０ｋａＢ．Ｐ．新仙女木事件，７．５０～５．００ｋｋＢ．Ｐ．重要降温事件和７．３７～６．３５ｋａＢ．Ｐ．大暖期高湖面事件），并预测未来全球长周期（１０００ａ以上）气候演变趋势─—渐冷。

RECORDS OF THE STABLE ISOTOPE OF OXYGEN AND CARBON AS WELL AS PALAEOCLIMATIC STUDIES IN YIKEZHAO LEAGUE LAKES OF INNER MONGOLIA SINCE LATE QUATERNARY PERLOD

Abstract the peper the change curves of stable isotope of oxygen and carbon have been drawn on the basis of measured data of the 340 samples of oxygen and carbon isotopes of the six hole cores (He01, He02, Ca01, Ba01, Ha01 and Ya02) in thefive salt lakes Yikezhao argue of inner Mongolia since 23 kaB. P. According to records of the stable isotopes, it indicated that the δ18O variations of salt lake water body are mainly controlled by evaporation and desalination, but the δ13C value fluctuations are mainly restricted by TDIC (Total Dissolved inorganic Carbon)changes and carbon exchanges between the lake water body and atmosphere. The water body environment of salt lakes has been clearly fluctuated up to the 17 times during 23 ha and the climatic variation laws have been brought, e. g. Late Pleistocene. Each -cold wet, Lower Holocene Epoch-warm wet, and Middle-Upper Holocene Epoches-warm (cold deviation) dry, and the three main climatic events have been discovered, e. g. Younger Dryas (10. 80--10. 50kaB. P. ), important droped events in temperature (7. 50--5. 00 kaB. P. ) and high lake level event in the major warm period (7. 37 -- 6. 35 kaB. P. ) as well as the global climatic developing trend has been determined on the long period, e. g. it is getting cold