Groundwater fluctuations in heterogeneous coastal leaky aquifer systems

Abstract

Abstract. In the past, the coastal leaky aquifer system, including two aquifers and an aquitard between them, was commonly assumed to be homogeneous and of infinite extent in the horizontal direction. The leaky aquifer system may however be heterogeneous and of finite extent due to variations in depositional and post depositional processes. In this paper, the leaky aquifer system is divided into several horizontal regions for the heterogeneous aquitard and underlying aquifer. A one-dimensional analytical model is developed for describing the head fluctuation in such a heterogeneous leaky aquifer system. The hydraulic head of the upper unconfined aquifer is assumed constant. It is found that both the length and location of the discontinuous aquitards presented in the coastal area have significant effects on the amplitude and phase shift of the head fluctuation in the lower aquifer. In addition, the influence of the formation heterogeneity on the spatial head distribution is also investigated.

The Impact of the Degree of Aquifer Confinement and Anisotropy on Tidal Pulse Propagation

“…There are numerous analytical solutions describing water table fluctuations in response to tidal forcing in a neighboring surface water body. These were derived for confined aquifers (Jacob 1950;Ferris 1951;van der Kamp 1972;Song et al 2007;Guo et al 2010), leaky confined aquifers (Jiao and Tang 1999;Jeng et al 2002;Chuang and Yeh 2007;Xia et al 2007;Chuang and Yeh 2008;Sun et al 2008;Chuang et al 2010;Chuang and Yeh 2011), and unconfined aquifers (Li et al 2000;Teo et al 2003;Song et al 2007;Chang et al 2010;Yeh et al 2010). Although multidimensional sophisticated analytical solutions exist for complex aquifers, a simple 1D Jacob-Ferris model assuming a semi-infinite, homogeneous, isotropic, and confined aquifer with a vertical bank submitted to sinusoidal wave variation has been widely used for estimating D (Erskine 1991;Millham and Howes 1995;Trefry and Johnston 1998;Schultz and Ruppel 2002;Jha et al 2003;Trefry and Bekele 2004;Zhou 2008;Rotzoll et al 2013;Zhou et al 2015).…”

An application of fluorescent tracer to groundwater tracking

“…Aquifer heterogeneity has a direct impact on hydraulic conductivity [15,16,17], which is determined by soil composition, porosity, particle size and shape, etc. [18].…”

Rainfall infiltration‐derived submarine groundwater discharge from multi‐layered aquifer system terminating at the coastline

“…The system satisfies the following assumptions: (1) All the formations extend landward for a distance L * and have vertical ocean–land interface at the coastline; the bottom of the leaky confined aquifer is impermeable. Vertical ocean–land interface was used in previous studies (Jeng et al , 2002; Li and Jiao, 2003; Chuang and Yeh, 2008; Ren et al , 2008; Rotzoll et al , 2008; Carol et al , 2009; Chuang et al , 2010; Yeh et al , 2010). (2) Each layer is homogeneous, isotropic and has horizontal interface with its adjacent layer.…”