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中国气候是以东亚夏季季风与冬季季风季节性交替为特征.所以黄土一古土壤的剖面记录为这种交替留下了一个极好的长期的替代性记录.由降水量驱动的成土作用是产生超细磁性矿物的主要原因,而这些极细的磁性物质强烈的影响着黄土序列中磁化率强度的信号.磁化率的变化与全球海洋δ~(18)O记录变化密切相关,并且还被用作夏季季风强度变化的参数,而夏季季风是随着轨道驱动力控制的太阳辐射量而变化.中国的现代尘暴和尘降事件主要发生在冬春季,与强大的西北风有关,历史上它们又与干冷时期有关.当风最强时,粉尘中的粗组份也就最多.据此可推断黄土记录中的粒径峰值记录了冬季季风增强的时期,因而也记录了搬运粉尘的风力增强时期.马兰黄土(末次冰期)在粒径与厚度上的区域性变化意味着是由西北风系的沉积引起的,其方向可与现代冬季季风平均风向相匹配.
China’s climate is characterized by the seasonal alternation of the East Asian summer monsoon and the winter monsoon, so profile records of an ancient loessial soil leave an excellent long-term alternative record for this alternation. The precipitation-driven diagenesis is These ultrafine magnetic materials strongly influence the signal intensity of the magnetic susceptibility in the loess sequence.The change of the magnetic susceptibility is closely related to the δ 18 O recording changes in the global oceans, Is used as a parameter for the change of summer monsoon intensity, while the summer monsoon varies with the amount of solar radiation controlled by orbital driving force.Modern dust storms and dustfall events in China occur mainly in winter and spring, which are related to the strong northwesterlies, and historically they Which is also related to the dry and cold periods, and when the wind is the strongest, the coarse component in the dust is also the largest, and thus the peak of grain size in the loess record can be deduced to record the period of enhancement of the winter monsoon and thus the wind power of handling dust is also recorded Period.The regional variation in grain size and thickness of the Malan loess (last glacial stage) means that it is caused by the deposition of the northwesterly wind system and its direction can be compared with that of the modern winter monsoon mean wind To match.