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通过对黄土高原中北部金丁镇马兰黄土中磁化率、Rb/Sr、全铁含量(TFe)与化学蚀变指数(CIA)等气候指标测试分析,并结合光释光年代学数据,着重地探讨了金丁剖面黄土地层记录的MIS3阶段气候变化特征。研究表明,金丁剖面MIS3阶段总体气候特征温湿,冷暖气候频繁波动,可进一步划分为5个阶段:51.6~44.9ka B.P.,弱温湿;42.0~39.9ka B.P.,中等温湿;37.4~27.8ka B.P.,相对强温湿;以及44.9~42.0ka B.P.和39.9~37.4ka B.P.两个冷干期。金丁剖面MIS3温湿气候成因机制的初步探讨认为北半球太阳辐射量增加导致的增温作用更直接,而高纬驱动与低纬过程耦合作用机制尚待开展进一步研究工作。
Based on the testing and analysis of the magnetic susceptibility, Rb / Sr, total iron content (TFe) and chemical alteration index (CIA) in the Malan loess of Jinding town in the north-central Loess Plateau, combined with the photoluminescence chronological data, The characteristics of climate change in the MIS3 stage recorded by loess strata in the Jinding section are discussed. The results show that the overall climatic characteristics of MIS3 in the Jinding section are warm and wet and fluctuate frequently in the warm and cold climate, which can be further divided into five stages: 51.6 ~ 44.9ka BP, weak warm wet, 42.0 ~ 39.9ka BP, moderate warm wet, 37.4 ~ 27.8 ka BP, relatively strong temperature and humidity; and 44.9 ~ 42.0ka BP and 39.9 ~ 37.4ka BP two cold dry period. The preliminary study on the genesis mechanism of MIS3 warm and humid climate in the Jinding section suggests that the warming effect caused by the increase of solar radiation in the northern hemisphere is more direct. However, the coupling mechanism between high latitude driving and low latitude processes remains to be further studied.