SPRING-NEAP TIDAL WATER TABLE FLUCTUATIONS IN A COASTAL AQUIFER: BEACH SLOPE-SEEPAGE FACE EFFECTS

摘要

Spring-neap tidal water table fluctuations (SNTWF) are oscillations of a period of approximately 14.79 days. These oscillations propagate much further inland than semi-diurnal and diurnal signals. Previous studies have shown that SNTWF are generated as a result of interactions between semi-diurnal lunar and solar tidal oscillations, induced by the moving seaward boundary condition. This paper investigates how the formation of seepage faces results in a spring-neap forcing oscillation on the boundary, and how the propagation of this signal in the aquifer also leads to SNTWF.