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The contents and distributions of CaCO3, Fe2O3, FeO and free Fe2O3 in the Weinan loess section of Shaanxi Province of China were investigated through dense sampling. The re-sults show that the contents of CaCO3 and the ratio of Fe2O3/FeO may be chosen as proxy in-dices for the precipitation and temperature changes in the formation time of the strata, respec-tively. According to these geochemical indices, six stages of palcoclimate evolution are proposed in this region since 142 ka B. P., and secondary climate changes are discussed as well based on the curves of geochemical indices.
The contents and distributions of CaCO3, Fe2O3, FeO and free Fe2O3 in the Weinan loess section of Shaanxi Province of China were investigated through dense sampling. The re-sults show that the contents of CaCO3 and the ratio of Fe2O3 / FeO may be chosen as proxy in-dices for the precipitation and temperature changes in the formation time of the strata, respec-tively. According to these geochemical indices, six stages of palcoclimate evolution are proposed in this region since 142 ka BP, and secondary climate changes are discussed as well based on the curves of geochemical indices.