Behavior of rare earth elements in granitic profiles, eastern Tibetan Plateau, China

• 作者: Lifeng Cui Zhiqi Zhao Congqiang Liu Sheng Xu Taoze Liu Chenglong Tu Hu Ding
• 来源期刊: 地球化学学报(英文）
• 关键词: Chemical weathering Eu anomaly Critical zone Soil weathering
• 年，卷（期）: 2017,（3）
• 页码范围: 552-555
• 页数: 3页
• 语种: 英文
• DOI: 10.1007/s11631-017-0234-7

摘要

Rare earth elements (REEs) can record geologic and geochemical processes. We studied two granitic regolith profiles from different climatic zones in eastern Tibetan Plateau and found that (1) ΣREEs ranged from 275.33 mg/kg 119.65 In Profile ND and to 5.11-474.55 mg/kg in profile GTC, with average values of 205.79 and 161 mg/kg, respectively. ΣREEs was higher in accumulation horizon and semi-regolith; (2) Influenced by climate, the fractionation of light and heavy REEs (LREEs and HREEs) varied during weathering. The ratio of LREEs/HREEs in pedosphere was higher than semi-regolith in tropical profile; (3) A negative Eu anomaly in both profiles was the result of bedrock weathering. A positive Ce anomaly was observed in all layers of profile ND, and only in the upper 100 cm of profile GTC. This indicates that redox conditions along the regolith profile varied considerably with climate. (4) Normalized by chondrite, LREEs accumulated much more than HREEs; REE distribution curves were right-leaning with a V-type Eu anomaly in both profiles.