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陕西岐山五里铺全新世黄土剖面层次结构清晰完整。通过对该剖面Rb、Sr含量和磁化率系统测定表明 ,黄土中Rb、Sr含量和Rb/Sr值明显不同于古土壤。它们作为气候替代指标比磁化率更灵敏 ,分辩率更高。Rb、Sr高含量及低Rb/Sr值指示冬季风占优势的干旱期 ,相对低的Rb、Sr含量及高的Rb/Sr值指示夏季风占优势的湿润时期。揭示在大约 6 0 0 0～ 5 0 0 0aBP曾出现一次以干旱为特征的明显气候恶化期 ,使全新世“大暖期”分裂形成两个主要的成壤期。黄土高原南部自全新世以来 ,经历了黄土沉积→土壤发育→黄土覆盖→土壤再度发育→黄土堆积及现代表土的发展演化阶段。
Shaanxi Qishan Wuli Paleo-Holocene loess profile clear and complete hierarchy. By the Rb, Sr content and magnetic susceptibility measurements of this section, the content of Rb and Sr and the value of Rb / Sr in loess are obviously different from those in paleosol. They are more sensitive and susceptible to magnetic susceptibility as a surrogate for climate. Rb, Sr and low Rb / Sr indicate the dominance of the winter monsoon. Relatively low Rb and Sr contents and high Rb / Sr values indicate wet periods dominated by the summer monsoon. Revealing that a clear climate deterioration period characterized by drought occurred in about 600 ~ 50000 a BPH, resulting in the division of the Holocene “Megathermal Period” into two major soil-forming periods. Since the Holocene, the southern Loess Plateau has undergone the stages of loess sedimentation → soil development → loess cover → re-development of soil → loess accumulation and the development and evolution of modern topsoil.