中国黄土区第四纪古气候变化

本文论述了,根据我国黄土与古土壤的风化指数、等温剩余磁化强度和孢粉的变化,可以肯定黄土是冰期形成的,古土壤是间冰期形成的,而且这种冷一暖气候的循环变化,在中国黄土区发生过23次。古气候变化界线的古地磁年代、古土壤的热释光年代同终止点(termination)的平均年代值基本一致,表明黄土中的古气候记录和深海岩芯V28—239的氧同位素气候期,能很好地对比起来。因此,可以认为位于黄土高原中部的陕西洛川和西安附近的黄土-古土壤系列,不但可以作为我国的标准古气候地层系列,而且在世界上也是典型的。     

CHANGES OF QUATERNARY CLIMATE OF LOESS DISTRICT IN CHINA

On the basis of the data of sporo-pollen analysis, the weathering index of loess and paleosol layers and the climatic differences between the periods of the formation of loess and paleosol as reflected by intensities of natural remanent magnetization of loess and paleosol, it may be confirmed that the loess layers represent the climate of glacial stages, while paleosol was formed during interglacial stages. The climatic changes in the loess area of China have undergone 23 cycles which were combined with the paleomagnetic dating. TL ages of paleosol layers and the average ages of termination could be excellently correlated with the δ~(18)O stages of deep sea core V_(28-239). Thus, it may be recognized that the Luochuan and Xi'an loess-paleosol sequences are the typical climatostratigraphy in China and even in the world.