Environmental Changes Recorded by Major Elements in Loulan Stupa Section during Early-Middle Holocene

Holocene palaeoweathering conditions and environmental changes of Loulan (楼兰) Stupa Sec-tion were reconstructed by major elements analysis results and optical stimulated luminescence dating results. Major element results show source rock change little, with the composition equivalent to granodiorite. The low R value and high CIA (chemical index of alteration) value indicating the section at primary weathering phases. The muddy silt and silty clay have low R value and high CIA value and total iron content. In contrast, the sandy clay silt and sandy silt have high R value and low CIA and total iron value. Deglaciation time climate was relatively humid. In comparison to previous and posterior hiatus, the Middle-Holocene climate was relatively wet but still displayed high-frequency and high-amplitude fluctuations.