Hydraulic head response of a confined aquifer influenced by river stage fluctuations and mechanical loading

作者：Pacheco F A L^*; Fallico C

来源：Journal of Hydrology, 2015, 531: 716-727.

DOI：10.1016/j.jhydrol.2015.10.055

• Hydraulic head
• Mechanical loading
• River stage fluctuation
• Hydraulic diffusivity
• Flow modeling

The response to river stage fluctuation of a drilled well penetrating a confined aquifer was simulated using a stream-aquifer interaction algorithm. Because the confined aquifer is overlaid by a water table aquifer, the algorithm was coupled with formulae used to correct the heads for mechanical loading. The coupling of stream-aquifer interaction and mechanical loading models was tried for the first time in this study. The test site was a drilled well installed on the Montalto Uffugo aquifer located at the Calabria University groundwater test field (Calabria region, south of Italy). This aquifer comprises a 44 m-thick sand bank bounded on bottom and top by clay layers and covered by a 7 m-thick sandy conglomerate, being adjacent to the Mavigliano River. Overall, the head changes caused by a river stage raise represented a contribution of 493-57.8% to the total head, while mechanical loading accounted for the remaining 50.7-32.2%. The loading was triggered by a sequence of short-spaced rainfall events lasting for a total of 167 days, which caused recharge to the unconfined aquifer thickening the water column by some 3.1 m.

• 出版日期2015-12