Seminar

Groundwater level fluctuation, as a basic and intuitive form of groundwater dynamics, plays an important role in the study of aquifer systems. Besides the macro dynamic of groundwater level, such as rainfall recharge and pumping drainage, micro factors (tidal effect and atmospheric pressure) also affect its fluctuation. Variations of water mass loading and unloading above the aquifer surface have been presented in diverse hydrogeological environments but frequently neglected when assessing hydrodynamic condition. Here we present high-frequency groundwater measurements over a winter period from the tropical Pearl River Delta Aquifer System, the typical aquifer in south China. The aquifer poroelastic response to changes in water loading by tidal effect and atmospheric pressure was interpreted as main account of groundwater level fluctuations. This study highlights the direct and quantitative identification of loading effects on groundwater levels, which has the implications for comprehensive hydrological and geochemical investigations in the Pearl River Delta Aquifer System.

Additional information: Mr. Shengchao YU, shchyu@connect.hku.hk