Groundwater circulation and hydrogeochemical evolution in Nomhon of Qaidam Basin, northwest China

Journal of Earth system science

Ge Zhang3 2¹  Jingli Shao1 2²  Yali Cui1²  Yong Xiao1²  Qiulan Zhang1² 

[1] Xi’an Center of Geological Survey, China Geological Survey, Xi’an 710054, China.$$;School of Water Resources and Environment, China University of Geosciences, Beijing 100083, China.$$

关键词: Hydrochemistry;    groundwater circulation;    isotopes;    water–rock interaction;    Qaidam Basin.;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

In this study, analysis of hydrogeological conditions, as well as hydrochemistry and isotopic tools were used to get an insight into the processes controlling mineralization, recharge conditions, and flow pattern of groundwater in a typical arid alluvial-lacustrine plain in Qaidam Basin, northwest China. Analysisof the dissolved constituents reveals that groundwater evolves from fresh water (TDS=300–1000 mg/l) to saline water (TDS ≥5000 mg/l) along the flow paths, with the water type transiting from HCO ₃•Cl– Na•Mg to HCO ₃•Cl–Na, and eventually to Cl–Na. Groundwater chemical evolution is mainly controlled by water–rock interaction and the evaporation–crystallization process. Deuterium and oxygen-18 isotopes in groundwater samples indicate that the recharge of groundwater is happened by meteoric water andglacier melt-water in the Kunlun Mountains, and in three different recharge conditions. Groundwater ages, estimated by the radiogenic (³H and ¹⁴C) isotope data, range from present to Holocene (~28ka). Based on groundwater residence time, hydrogeochemical characteristics, field investigation, and geological structure distribution, a conceptual groundwater flow pattern affected by uplift structure is proposed, indicating that shallow phreatic water is blocked by the uplift structure and the flow directionis turned to the northwest, while high pressure artesian water is formed in the confined aquifers at the axis of the uplift structure.

【 授权许可】

Unknown