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对黄土高原中部洛川黄土堆积进行了系统的粒度和磁化率测量，以黄土－古土壤中的粗颗粒组分，即＞３０μｍ颗粒的百分含量作为冬季风强度代用指标，根据一个独立的时间标尺，发现在１４５～１６５、２４０～２８０、３２０～３５０、３９０～４４０、６００～６４０、８６０～８９０、９００～９３０和１３３０～１４００ｋａＢ．Ｐ．东亚冬季风强度存在千年尺度快速变化的特征，冬季风加强事件的持续时间在１．４～７．２ｋａ之间，变化幅度也不相同；周期分析结果表明，这些古气候变化存在１．８９～４．０ｋａ之间的周期，由于时间标尺的精度还有待于进一步提高，在这里没有把冬季风强度变化与北大西洋沉积物记录的古气候事件进行对比，但是，实验结果证明在早、中更新世的某些阶段东亚冬季风强度存在快速变化的现象
Systematic particle size and magnetic susceptibility measurements of Luochuan loess accumulation in the central Loess Plateau were carried out. Taking the percentage of coarse particles in loess-paleosol, that is, the percentage of particles> 30μm, as proxy of winter monsoon intensity, according to an independent time The scale was found to be 145-165, 240-280, 320-350, 390-440, 600-640, 860-890, 900-930 and 1330-1400 kaB. P. The intensity of the winter monsoon in East Asia has the characteristics of fast changing on a thousand-year scale. The duration of the winter monsoon strengthening event is between 1.4-7.2 ka, and the variation range is not the same. The periodic analysis shows that there are 1.89 ~ In the period between 4.0 and 4.0 ka, the precision of the time scale needs to be further improved. The change of the winter monsoon intensity is not compared with the paleoclimate recorded by the North Atlantic sediment. However, the experimental results show that in the early and middle update The intensity of East Asian winter monsoon varies rapidly at some stage in the world