Geochemical record of rapid climate change and chemical weathering in a semi-arid area, northeastern Tibetan Plateau
- Resource Type
- Article
- Authors
- Wenxiang Zhang; Hucai Zhang; Jie Niu; Guoliang Lei; Fengqin Chang
- Source
- Geosciences Journal, 24(6), pp.723-732 Dec, 2020
- Subject
- 지질학
- Language
- English
- ISSN
- 1598-7477
1226-4806
Lacustrine deposits can provide insight into chemical weathering and climate change. Based on the analysis of the element concentrations and parameters of the acid-leaching residual fractions (AR) in the lacustrine deposits of the Qaidam Basin (QB), chemical weathering and paleoclimate changes in the northeastern Tibetan Plateau (NETP) have been studied. The results show that the characteristics of trace element concentrations exhibit two kinds of patterns by normalized element arbitrary units (a.u.). The rare earth element (REE) distribution patterns are moderately rich in light rare earth elements (LREEs) with slightly right-tilting and negative Eu anomalies. Triangular plots of the REEs and (La/Yb)n-ΣREE suggest that the sediments have a similar source. The geochemical records of climate proxies indicated warm-wet climate stages during 45.1–31.6 cal. ka BP., further proving that a megalake stage existed in the semi-arid area in marine isotope stage (MIS) 3. Strong evaporation resulted in a high paleolake level history in the northeastern Tibetan Plateau after the late period of MIS 3. Meanwhile, the geochemical records of the Qaidam Basin are synchronous with the global records.