The Periodicity of Organic Elements in the Yangguo Loess Section of Weinan and Paleoclimatic Evolution

Key words: 
• periodicity paleoclimate evelution /
• organic components /
• yanggou loess section /

Abstract: By now the Yangguo loess section is one of the most complete sections of the last 150, 000years. In this paper, the organic components that are bound up with the climatic variation have been studied by the mathematical methods. It can be seen that the probability distributions of loess and Paleosol from the Yangguo section are normal distributions which are differentiated by the mean and standard daviations, respectively. Four cycles stable which are 67.1Ka, 33. 5Ka, 25. 2Ka and 18. 3Ka, have also been recognized. The four periods mentioned above are consistent with the variations of the chemical components from the Luochuan section, and in line with oxygen isotopic values (δ¹⁸O) for deep-sea drilled cores and those calculated by Milankovitch for elements of Earth's orbits. That is because that the paleoclimatic evolution in the Quaternary period was controlled by some astronomical factors.