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毛乌素沙漠萨拉乌苏河流域米浪沟湾剖面时代上属末次间冰期的MGS5层段可以进一步划分为5a—5e亚段。其中5a,5c和5e亚段以河湖相和古土壤为主要特征,其CaCO_3含量主体呈现峰态;5b和5d亚段以风成沙丘砂沉积为主,CaCO_3含量主体呈现谷态。研究表明,末次间冰期毛乌素沙漠冬季风盛行时期,沙丘砂强烈堆积,CaCO_3大量迁移;夏季风盛行时期河湖相和古土壤发育,CaCO_3大量聚集。研究还发现,MGS5各个亚段CaCO_3记录的冬夏季风环境与格陵兰冰芯氧同位素5a 5e亚段在时间—气候性质上的变化节奏相当一致。这可能说明,末次间冰期毛乌素沙漠的演化主要受北半球冰量增减导致的东亚冬、夏季风强弱所控制。
The MGS5 interval, which belongs to the last interglacial period in the Mi Langgouwan section of the Sara Wusu River basin in the Mu Us Desert, can be further divided into sub-sections 5a-5e. The sub-sections 5a, 5c and 5e are mainly characterized by river-lake facies and paleosol, and the main body of CaCO_3 shows a kurtosis. In sub-section 5b and 5d, the sediments of aeolian sand dunes are dominant, and the main body of CaCO_3 presents as a valley. The results show that during the last interglacial Mu Us Desert winter monsoon prevailed, sand dunes strongly accumulated and CaCO_3 migrated in a large amount. During the prevalence of summer monsoon, the lacustrine facies and palaeosol developed and CaCO_3 aggregated abundantly. The study also found that the temporal and climatic changes in the winter-summer monsoon environment recorded by CaCO_3 in each sub-section of MGS5 are in good agreement with that of the Greenland ice core oxygen 5-e 5e sub-section. This may indicate that the evolution of the Mu Us Desert in the last interglacial period was mainly controlled by the intensity of the East Asian winter and summer monsoons caused by the increase and decrease of ice volume in the northern hemisphere.