Detecting inter-aquifer leakage in areas with limited data using hydraulics and multiple environmental tracers, including He-4, Cl-36/Cl, C-14 and Sr-87/Sr-86


Date

2017-11

Publication Type

Journal Article

ETH Bibliography

yes

Citations

Altmetric

Data

Abstract

The investigation of regionally extensive groundwater systems in remote areas is hindered by a shortage of data due to a sparse observation network, which limits our understanding of the hydrogeological processes in arid regions. The study used a multidisciplinary approach to determine hydraulic connectivity between the Great Artesian Basin (GAB) and the underlying Arckaringa Basin in the desert region of Central Australia. In order to manage the impacts of groundwater abstraction from the Arckaringa Basin, it is vital to understand its connectivity with the GAB (upper aquifer), as the latter supports local pastoral stations and groundwater-dependent springs with unique endemic flora and fauna. The study is based on the collation of available geological information, a detailed analysis of hydraulic data, and data on environmental tracers. Enhanced inter-aquifer leakage in the centre of the study area was identified, as well as recharge to the GAB from ephemeral rivers and waterholes. Throughout the rest of the study area, inter-aquifer leakage is likely controlled by diffuse inter-aquifer leakage, but the coarse spatial resolution means that the presence of additional enhanced inter-aquifer leakage sites cannot be excluded. This study makes the case that a multi-tracer approach along with groundwater hydraulics and geology provides a tool-set to investigate enhanced inter-aquifer leakage even in a groundwater basin with a paucity of data. A particular problem encountered in this study was the ambiguous interpretation of different age tracers, which is attributed to diffusive transport across flow paths caused by low recharge rates.

Publication status

published

Editor

Book title

Volume

25 (7)

Pages / Article No.

2031 - 2047

Publisher

Springer

Event

Edition / version

Methods

Software

Geographic location

Date collected

Date created

Subject

Australia; Aquitard; Arid regions; Hydrochemistry; Inter-aquifer leakage/cross formational flow

Organisational unit

03946 - Schönbächler, Maria / Schönbächler, Maria check_circle
03956 - Vance, Derek / Vance, Derek check_circle

Notes

Funding

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