关键词: 关中泾阳塬, 全新世, 磁化率, 古气候, 黄土

Abstract: By lithological description, classification and correlation of the Holocene loess-palaeosol stratum in typical sections of loess plateau in southern Zhaitou and Xinzhuang villages in Jingyang county, Guanzhong area of the Sannxi Province, and combined with the age determination of AMS14C and age data obtained by other scholars, the loess deposition age sequence of the studied area is established. Based on the character of the susceptibility curve, a substitution indication of ancient climate, the authors can expound the changing regularity of this substitution indication in the section. At the same time,the authors can make inference on the strength and changing character of the winter and summer monsoons in East Asian reflected by the loess section. The available evidence suggests that the fluctuation of the ancient climate in the Guanzhong area have the consistent trend with that in Northwest China and the globe. During Holocene, under the general global climate changing tendency, the climate evolution of the Guanzhong area is represented by the nature of cycle, unstability and trend. The susceptibility curve of the section is also compared with the temperature curve reconstructed from sporopollen by other scholars. On the base of careful analysis and verification, the palaeoclimate stage features during the Holocene in the Guanzhong area are thoroughly discussed. Seven climate stages in most recent 10000 years have been suggested and they are: stage 1, 10.0-9.0 kaB.P., being a conversion stage when the climate turned from cold to warm; Stage 2, 9.0-7.0 kaB.P., a frequently fluctuated climate stage; Stage 3, 7.0-6.0 kaB.P., a warm phase; Stage 4, 6.0-5.0 kaB.P., a mild warm stage; Stage 5, 5.0-3.4 kaB.P., a turbulent, warm and cold alternated stage; Stage 6, 3.4-2.0 kaB.P., a stage with temperature decreased at first and then increased and finally； Stage 7, 2.0 kaB.P. to present, a warm semi-humid and semi-arid stage.

Key words: loess plateau of Jingyang, Guanzhong, Holocene, susceptibility, palaeoclimate, loess