When Do Complex Transport Dynamics Arise in Natural Groundwater Systems?. Issue 2 (10th February 2020)

• Record Type: Journal Article
• Authors: Wu, J.; Lester, D. R.; Trefry, M. G.; Metcalfe, G.
• Is Part Of: Water resources research. Volume 56:Issue 2(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-02-10
• Subjects: Darcy flow -- tidal aquifer -- poroelastic -- solute transport -- groundwater; Hydrology -- Periodicals; 333.91
• DOI: 10.1029/2019WR025982
• Languages: English
• ISSNs: 0043-1397

Abstract

Abstract: In a recent paper (Trefry et al., 2019, https://doi.org/10.1029/2018wr023864 ), we showed that the interplay of aquifer heterogeneity and poroelasticity can produce complex transport in tidally forced aquifers, with significant implications for solute transport, mixing, and reaction. However, what was unknown was how broadly these transport dynamics can arise in natural groundwater systems and how these dynamics depend upon the aquifer properties and tidal and regional flow characteristics. In this study we answer these questions through parametric studies of these governing properties. We uncover the mechanisms that govern complex transport dynamics and the bifurcations between transport structures that depend upon changes in the governing parameters, and we determine the propensity for complex dynamics to occur in natural aquifer systems. These results clearly demonstrate that complex transport structures and dynamics may arise in natural tidally forced aquifers around the world, producing solute transport and mixing behavior that is very different to that of the conventional Darcy flow picture. Key Points: Transient Darcy flows can generate complex transport dynamics in heterogeneous compressible aquifers This complex transport can trap dispersing solutes for many years Global tidal maps indicate widespread potential for complex transport dynamics in coastal zones