一万年以来西安鱼包头黄土剖面磁化率的古气候环境再讨论

Re-discussion on the palaeoclimate environment of susceptibility of Loess section since 10 KaBP in Xi'an Yubaotou

对西安地区全新世以来的环境演变特征进行研究,从而为预测西安地区乃至中国和全球未来环境的发展趋势提供依据。通过对西安神禾塬鱼包头村典型剖面全新世黄土-古土壤地层的岩性描述、地层划分和对比,结合泾阳县新庄村AMS14C的年代测定和其他学者的测年数据,建立了该地区全新世以来黄土沉积年代序列。根据磁化率气候替代指标显示的曲线特征,阐述了这一替代指标在剖面上的变化规律,探讨了该黄土剖面所反映的东亚冬、夏季风强弱变化特点,论证和详细分析了西安地区全新世以来环境变化的特征和规律,进而对该剖面磁化率曲线特征与其他学者的孢粉谱建立的温度曲线对比。对西安地区全新世以来古气候的阶段性进行了详细分析和论证。将西安地区10000年以来的气候演变划分为7个气候阶段。

The characteristics of the environment evolution in Xi＇an area during the Holocene were researched, providing a basis for future environment development trends for Xi＇an area and China and the global were predicted. Loess deposition age sequence during the Holocene in the region was established by the description of rock character of loess - palaeosol stratum, the partition and contrast of stratum of section in Yubaotou village of Xi＇an Shen Heyuan, and with the combination of age measuring of AMS^14C in Xin Zhuang village of Jing Yang county and other scholarsiesting datums. According to the characters of the curve expressed by substitution indication of climate of susceptibility, we expounded the changing regularity of this substitution indication in the section. At the same time, we explored the strength changing characters of winter and summer monsoon in East Asian reflected by the loess section, demonstrated and minutely analyzed the characters and laws of environment changing in Xi＇an area during the Holocene, then the character of the susceptibility curve of this section was compared with temperature curve of sporopollen spectrum established by other scholars. At the same time, on the base of careful analysis and verification to the palaeoclimate stage trait during the Holocene in Xi＇an area,7 climate stages nearly 10000 years in Xi＇an area were raised.