Characteristics of groundwater in Northeast Qinghai-Tibet Plateau and its response to climate change and human activities: A case study of Delingha, Qaidam Basin

Abstract

Delingha is located in the northeast margin of Qaidam Basin. Bayin River alluvial proluvial fan is the main aquifer of Delingha, in which groundwater generally flows from north to south. The hydrochemistry results showed that two different hydrochemical evolution paths formed along southeast and southwest directions, respectively. Cl-Na type groundwater was formed in front of Gahai Lake, and SO4·HCO3-Na·Ca type groundwater was formed in front of Keluke Lake. The results of deuterium (D) and 18O revealed that the groundwater mainly originated from the continuous accumulation of precipitation during geological history under cold and humid climate conditions. In addition, results of 14C indicated that the groundwater age was more than 1140 years, implying relatively poor renewal capability of regional groundwater. Moreover, our numerical modeling results showed that the regional groundwater level will continue to rise under the warm and humid climate conditions.© 2021 China Geology Editorial Office.

Keywords

• Groundwater
• Global climate change
• Hydrochemistry
• Groundwater circulation
• Groundwater age
• Groundwater level rising