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洛川、宜川及渭南黄土剖面古风化强度的研究揭示出,在L1和L2中记录了一系列干冷气候事件。它们多数发生于黄土与古土壤的交界处,以5000—10000a的间隔叠置于明显的准20000a岁差周期上。前六个事件的时代与北大西洋的Heinrich事件大致相当。上述结果表明,Heinrich事件在东亚季风区有明显印迹,且类似事件在相当于深海氧同位素阶段6的黄土中也存在。最后两个事件时我国的古环境状况可能比末次盛冰期还要干冷些。这些事件出现的地层层位似乎表明,它们易发生于由地球轨道变化引起的气候转变时期。
A study of the paleo-weathering intensity of the Luochuan, Yichuan and Weinan loess sections revealed that a series of dry and cold climate events were recorded in L1 and L2. Most of them occur at the juncture of loess and ancient soils, superimposed at intervals of 5000-10000 a on obvious periods of quasi 20000 years of age. The times of the first six events are roughly the same as the Heinrich events of the North Atlantic. The above results show that the Heinrich event is clearly imprinted in the East Asian monsoon region and that similar events are also present in loess equivalent to the deep-sea oxygen isotope stage 6. In the last two events, the paleoenvironment of our country may be even drier than the last ice age. The presence of these events seems to indicate that they are prone to periods of climate change caused by changes in the Earth’s orbit.